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101.
102.
Carlos Sainz Ismael Fuente Luis Quindós Jose Luis Gutierrez Jose Luis Arteche Luis Santiago Quindós 《Acta Geophysica》2010,58(5):957-962
People working with ionising radiation are receiving radiation coming from artificial and natural sources. In Spain, as in
many other countries, there is a serious control by the national authorities, Spanish Nuclear Safety Council, of the dose
the workers receive from artificial sources. However, until the publication of the European Basic Safety Standards Directive,
96/29/EURATOM, the old criteria referring to the “above natural background” were widely used. This directive was incorporated
to the Spanish legislation in July 2001 (BOE 178); in its Title VII it recommends to evaluate the dose coming from natural
sources and take it into account for establishing the safety criteria. It is noteworthy to assess the natural doses received
at homes and the dose received by workers of radioactive installations subject to regulations, and to compare the two results.
The social and economical implications of the results derived can be important in the practical application of the recommendations
included in the above-mentioned BOE 178 Directive. 相似文献
103.
Residual Exchange Flows in Subtropical Estuaries 总被引:1,自引:0,他引:1
Arnoldo Valle-Levinson Guillermo Gutierrez de Velasco Armando Trasviña Alejandro J. Souza Reginaldo Durazo Ashish J. Mehta 《Estuaries and Coasts》2009,32(1):54-67
Observations of residual exchange flows at the entrance to four subtropical estuaries, two of them semiarid, indicate that
these flows are mainly tidally driven, as they compare favorably with theoretical patterns of tidal residual flows. In every
estuary examined, the tidal behavior was that of a standing or near-standing wave, i.e., tidal elevation and tidal currents
were nearly in quadrature. The pattern of exchange flow that persisted at every estuary exhibited inflow in the channel and
outflow over the shoals. Curiously, but also fortuitously, this pattern coincides with the exchange pattern driven by density
gradients in other estuaries. The tidal stresses and the residual elevation slopes should be the dominant mechanisms that
drive such tidal residual pattern because the Stokes transport mechanism is negligible for standing or near-standing waves.
Time series measurements from the semiarid estuaries showed fortnightly modulation of the residual flow by tidal forcing in
such a way that the strongest net exchange flows developed with the largest tidal distortions, i.e., during spring tides.
This modulation is opposite to the modulation that typically results in temperate estuaries, where the strongest net exchange
flows tend to develop during neap tides. The fortnightly modulation on tidal residual currents could be inferred from previous
theoretical results because residual currents arise from tidal distortions but is made explicit in this study. The findings
advanced herein should allow the drawing of generalities about exchange flow patterns in subtropical estuaries where residual
flows are mainly driven by tides. 相似文献
104.
The Open-source Project for a Network Data Access Protocol (OPeNDAP) software framework has evolved over the last 10 years to become a robust, high performance, service oriented architecture for the access and transport of scientific data from a broad variety of disciplines, over the Internet. Starting with version 4.0 of the server release, Hyrax, has at its core, the Back-End Server (BES). The BES offers ease of programming, extensibility and reliability allowing added functionality especially related to high-performance data Grids, that goes beyond its original goal of distributed data access. We present the fundamentals of the BES server as a component based architecture, as well as our experiences using the BES to distribute data processing in Grid-oriented intensive parallel computational tasks. 相似文献
105.
Pablo Otero Manuel Ruiz-Villarreal Luz García-García Gonzalo González-Nuevo Jose Manuel Cabanas 《Ocean Dynamics》2013,63(1):115-129
The consequences of a stormy winter period (2009/2010) on the shelf and coastal dynamics off Northwest Iberia are analysed by using model results in combination with the set of available observations in the frame of the Iberian Margin Ocean Observatory (RAIA), a cross-border infrastructure among North Portugal and Galicia (Spain). During the study winter, the frequent arrival of weather fronts forced river plumes to flow along the inner shelf in a fast (>1 m?s?1) jet-like structure. The buoyant current strongly influenced the outer rías, the name of the estuaries in the region, where a strong decay of surface salinity (<10.5) has been observed. Once the weather front has passed, the wind reversal forced the offshore expansion of river plumes and also the development of a winter upwelling event. Thermohaline patterns in both model and observations revealed an intrusion of warm (>15 °C) and salty (>35.9) waters into the rías associated with the Iberian Poleward Current. Finally, some Lagrangian modelling experiments were performed to analyse the transport ability of the plume and the effect that could have had in the biological material trapped on it. The experiments reveal that an overall northward displacement of surface particles will be expected after several alternate wind events. 相似文献
106.
Jose A. Carnicero M. Concepción Ausín Michael P. Wiper 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(8):1991-2002
This paper proposes a nonparametric approach to estimating the dependence relationships between circular variables and other circular or linear variables using copulas. The proposed method is based on the use of Bernstein copulas which are a very flexible class of non-parametric copulas which allows for the approximation of any kind of dependence structure, including non symmetric relationships. In particular, we present a simple procedure to adapt Bernstein copulas to the circular framework and guarantee that the constructed bivariate distributions are strictly continuous. We provide two illustrative case studies, the first on the relation between wind direction and quantity of rainfall in the North of Spain and the second on the dependence between the wind directions in two nearby buoys at the Atlantic ocean. 相似文献
107.
Alejandro Marulanda Aguirre Omar Alfonso Fonseca Tobasura Omar Darío Cardona Arboleda 《水文科学杂志》2013,58(12):2179-2192
ABSTRACTThis paper presents the results of a hydrological study aimed at characterizing flood-prone areas in the urban growth zone in the city of Manizales based on the potential effects of melting of the Nevado del Ruiz glacier, in Caldas, Colombia. These results constitute a basis for decision making regarding possible urban growth zones in Andean areas that face risks from volcanic eruptions producing lahars and floods caused by glacier melt. Conservative estimates of extreme flows in the Chinchiná River in the urban growth area of El Rosario can be obtained by considering the effects of rain triggered by airborne particulate material following a volcanic explosion combined with the effects of glacier melt. The effects of global warming on tropical glaciers contribute to their retreat, leading to their disappearance. Therefore, the worst scenario would take place if these events occurred in the short term as glacier volume decreases with time.
Editor Z.W. Kundzewicz; Associate editor not assigned 相似文献
108.
In this study we analyze water level data from coastal tide gauges and deep-ocean tsunameters to explore the far-field characteristics of two major trans-Pacific tsunamis, the 2010 Chile and the 2011 Japan (Tohoku-oki) events. We focused our attention on data recorded in California (14 stations) and New Zealand (31 stations) as well as on tsunameters situated along the tsunami path and proximal to the study sites. Our analysis considers statistical analyses of the time series to determine arrival times of the tsunami as well as the timing of the largest waves and the highest absolute sea levels. Fourier and wavelet analysis were used to describe the spectral content of the tsunami signal. These characteristics were then compared between the two events to highlight similarities and differences between the signals as a function of the receiving environment and the tsunami source. This study provides a comprehensive analysis of far-field tsunami characteristics in the Pacific Ocean, which has not experienced a major tsunami in nearly 50 years. As such, it systematically describes the tsunami response characteristics of modern maritime infrastructure in New Zealand and California and will be of value for future tsunami hazard assessments in both countries. 相似文献
109.
AbstractThe Hilhorst model was used to convert bulk electrical conductivity (σb) to pore water electrical conductivity (σp) under laboratory conditions by using the linear relationship between the soil dielectric constant (εb) and σb. In the present study, applying the linear relationship εb–σb to data obtained from field capacitance sensors resulted in strong positive autocorrelations between the residuals of that regression. We were able to derive an accurate offset of the relationship εb–σb and to estimate the evolution of σp over time by including a stochastic component to the linear model, rearranging it to a time-varying dynamic linear model (DLM), and using Kalman filtering and smoothing. The offset proved to vary for each depth in the same soil profile. A reason for this might be the changes in soil temperature along the soil profile.
Editor D. Koutsoyiannis; Associate editor M.D. Fidelibus 相似文献
110.
Luis S. Quindos Poncela Carlos Sainz Fernandez Ismael Fuente Merino Jose L. Gutierrez Villanueva Alberto Gonzalez Diez 《Acta Geophysica》2013,61(4):848-858
Radon can be used as a naturally occurring tracer for environmental processes. By means of grab-sampling or continuous monitoring of radon concentration, it is possible to assess several types of dynamic phenomena in air and water. We present a review of the use of radon and its progeny at the University of Cantabria. Radon can be an atmospheric dynamics indicator related with air mass interchange near land-sea discontinuities as well as for the study of vertical variations of air parameters (average values of different types of stability: 131–580 Bq m?3). Concerning indoor gas, we present some results obtained at Altamira Cave (Spain): from 222 to 6549 Bq m?3 (Hall) and from 999 to 6697 Bq m?3 (Paintings Room). Finally, variations of radon concentration in soil (0.3 to 9.1 kBq m?3) and underground water (values up to 500 Bq l?1) provide relevant information about different geophysical phenomena. 相似文献