Stochastic　model　of　bedrock　earthquake　motion　and　determination　of　its　parameters     

牛荻涛 《地震学报(英文版)》1995,8(1):155-159

ＳｔｏｃｈａｓｔｉｃｍｏｄｅｌｏｆｂｅｄｒｏｃｋｅａｒｔｈｑｕａｋｅｍｏｔｉｏｎａｎｄｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｉｔｓｐａｒａｍｅｔｅｒｓＤｉ－ＴａｏＮＩＵ（牛荻涛）（Ｘｉ＇ａｎＵｎｉｖｅｒｓｉｔｙｏｆＡｒｃｈｉｔｅｃｔｕｒａｌＳｃｉｅｎｃｅａｎ...  相似文献   

Subvolcanic structure of the central dike swarm associated with the ring complexes in the Shitara district,central Japan     

Akira Takada 《Bulletin of Volcanology》1988,50(2):106-118

The Subvolcanic structure of the central dike swarm associated with the Miocene Otoge ring complex and the Shitara igneous complex, central Japan, has been reconstructed. The central dike swarm was supplied from several aligned magma reservoirs. Flow lineations observed at the margin of the dikes converge towards a region that is regarded as a magma reservoir about 1–2 km below present sea level. The minimum diameter of the magma reservoir corresponds to the width of the central dike swarm, estimated to be about 3–4 km. The inferred magma reservoir of the Otoge ring complex, may have a zoned structure, as suggested by the flow lineations of dikes and the arrangement of cone sheets. Felsic magma occupied the upper part, about 1–2 km below present sea level, and basic magma the lower part, deeper than 2 km. The centre of the Shitara igneous complex is interpreted to be composed of several other shallow magma reservoirs. The distribution pattern in plan view of the central dike swarm is summarized from the frequency of dikes (defined by the number of dikes per kilometre in the direction normal to the trend of the dike swarm) and the variations of the different properties of individual dikes along the dike swarm. It has a plane of symmetry normal to the dike swarm above the magma reservoir. The patterns critical to a general understanding of the dike formation are:

1.	A region of low dike frequency is present above the magma reservoir and a radial dike pattern occurs around the magma reservoir.
2.	From both sides of the magma reservoir, the axes of high dike frequency extend symmetrically along the central zone of the dike swarm.
3.	The number as well as the individual and total thickness of felsic dikes increases towards the magma reservoir.
4.	The number of basic dikes increases towards both sides of the magma reservoir, while the individual thicknesses of basic dikes increase with distance from the magma reservoir.

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Geomagnetic quiet day selection     

Jo Ann Joselyn 《Pure and Applied Geophysics》1989,131(3):333-341

Based on published literature and the response to a questionnaire sent to geomagnetic field, ionospheric and magnetospheric researchers, several methods of choosing periods of quiet conditions based on geomagnetic records, as well as other observed parameters, have been identified. Caveats with respect to using geomagnetic indices to select quiet periods include the following:

1.	Geomagnetic disturbances are strongly local. Even if the data from all available observatories indicate quiet behavior, there is the distinct possibility that some other location, not sampled, may be disturbed.
2.	Geomagnetic indices are convenient but imperfect indicators of geomagnetic activity. Indices based on a quiet-day reference level have uncertainties comparable to the threshold value for quiet conditions. Indices representing average conditions during a 24-hr UT day may not be appropriate.
3.	Geomagnetic activity does not fully reflect the range of possible factors that influence the ionosphere or magnetosphere.

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Derivation of Photosynthetically Available Radiation from METEOSAT data in the German Bight with Neural Nets   总被引：1，自引：0，他引：1  

Kathrin Schiller 《Ocean Dynamics》2006,56(2):79-85

Two different models, a Physical Model and a Neural Net (NN), are used for the derivation of the Photosynthetically Available Radiation (PAR) from METEOSAT data in the German Bight; advantages and disadvantages of both models are discussed. The use of a NN for derivation of PAR should be preferred to the Physical Model because by construction, a NN can take the various processes determining PAR on a surface much better into account than a non-statistical model relying on averaged relations.

Kathrin SchillerEmail:

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A model of producer incentives for livestock disease management     

Ram Ranjan  Ruben N. Lubowski 《Stochastic Environmental Research and Risk Assessment (SERRA)》2005,19(5):315-325

We examine the management of livestock diseases from the producers‘ perspective, incorporating information and incentive asymmetries between producers and regulators. Using a stochastic dynamic model, we examine responses to different policy options including indemnity payments, subsidies to report at-risk animals, monitoring, and regulatory approaches to decreasing infection risks when perverse incentives and multiple policies interact. This conceptual analysis illustrates the importance of designing efficient combinations of regulatory and incentive-based policies.

Ram RanjanEmail:

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Spatial random field simulation by a numerical series representation     

A. Oya  J. Navarro-Moreno  J. C. Ruiz-Molina 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(4):317-326

An approach to the simulation of spatial random fields is proposed. The target random field is specified by its covariance function which need not be homogeneous or Gaussian. The technique provided is based on an approximate Karhunen–Loève expansion of spatial random fields which can be readily realized. Such an approximate representation is obtained from a correction to the Rayleigh–Ritz method based on the dual Riesz basis theory. The resulting numerical projection procedure improves Rayleigh–Ritz algorithm in the approximation of second-order random fields. Simulations are developed to illustrate the convergence and accuracy of the method presented.

J. C. Ruiz-MolinaEmail:

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Characteristics of afferent activity of ampullary electroreceptors in catfish Parasilurus asotus     

Hong Zhu  Jiayu Zou  Fasheng Xia 《地震学报(英文版)》1992,5(2):399-405

The spontaneous and evoked activity of electroreceptors were electrophysiologically studied. The results are:

1.	The spontaneous discharge rate ranged from 15 to 85 imp/s with a mode of 50 imp/s for 126 organs of 18 animals.
2.	By analysis of periodic histograms and interspike interval histograms of responses to sinusoidal electric stimulations, the frequency response characteristic was determined. The frequency response curve shows a band pass type, the band width ranged from 5 Hz to 30 Hz and the best frequency is around 15 Hz.
3.	The thresholds of responses for 47 organs were measured by injection of sinusoidal current into the organs. The threshold values were less than 0.1nA (61μV/cm) for 35 organs (74%), and less than 0.01nA (6.1 μV/cm) for the rest of 9 organs (19%).

The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 380–386, 1991.  相似文献   

An analysis of the salt water inflow into the Baltic in 1975 to 1976     

Dr. Hans Ulrich Lass  Reinhard Schwabe 《Ocean Dynamics》1990,43(3):97-125

Time series measurements from light vessel and coastal stations in the transition area of the Kattegat and the Baltic Sea are analyzed for the period August 1975 to March 1976. The data consist of daily sampled salinities from different depth levels and daily means of sea levels, surface current, and wind, respectively. The purpose of this paper is to examine the dynamics of the mass- and salt-transport during a major salt water inflow.The principal conclusions of this paper are that

1)	the dynamics of the barotropic water exchange between the Kattegat and the Baltic Sea resembles that of a Helmholtz-resonator with a geostrophically controlled flow in the connecting channel;
2)	the water exchange is forced by both the east component of the windstress over the North Sea and the windstress component in 30o true over the Baltic Sea;
3)	the salinity in the upper layer of the Kattegat is governed by a permanent weak salt flux directed from the bottom to the surface layer and the outflow of less saline Baltic water into the upper layer of the Kattegat whereas the salinity of the Belt Sea is advected by the local currents along the main channel;
4)	the most favorable conditions for a major salt inflow are initially a mean sea level of the Baltic lowered by about 30 cm followed by west winds steadily increasing over the following several ten days. Moreover, the hitherto used definition of a major salt water inflow is discussed and an improved definition is proposed.

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Outlier detection with partial information: application to emergency mapping     

Davide D’Alimonte  Dan Cornford 《Stochastic Environmental Research and Risk Assessment (SERRA)》2008,22(5):613-620

This paper, addresses the problem of novelty detection in the case that the observed data is a mixture of a known ‘background’ process contaminated with an unknown other process, which generates the outliers, or novel observations. The framework we describe here is quite general, employing univariate classification with incomplete information, based on knowledge of the distribution (the probability density function, pdf) of the data generated by the ‘background’ process. The relative proportion of this ‘background’ component (the prior ‘background’ probability), the pdf and the prior probabilities of all other components are all assumed unknown. The main contribution is a new classification scheme that identifies the maximum proportion of observed data following the known ‘background’ distribution. The method exploits the Kolmogorov–Smirnov test to estimate the proportions, and afterwards data are Bayes optimally separated. Results, demonstrated with synthetic data, show that this approach can produce more reliable results than a standard novelty detection scheme. The classification algorithm is then applied to the problem of identifying outliers in the SIC2004 data set, in order to detect the radioactive release simulated in the ‘joker’ data set. We propose this method as a reliable means of novelty detection in the emergency situation which can also be used to identify outliers prior to the application of a more general automatic mapping algorithm.

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Davide D’AlimonteEmail:

Dan Cornford (Corresponding author)Email:

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Seismic vulnerability of lifelines in the greater Lisbon area     

João Azevedo  Luís Guerreiro  Rita Bento  Mário Lopes  Jorge Proença 《Bulletin of Earthquake Engineering》2010,8(1):157-180

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A multifractal formalism for vector-valued random fields based on wavelet analysis: application to turbulent velocity and vorticity 3D numerical data     

Pierre Kestener  Alain Arneodo 《Stochastic Environmental Research and Risk Assessment (SERRA)》2008,22(3):421-435

Extreme atmospheric events are intimately related to the statistics of atmospheric turbulent velocities. These, in turn, exhibit multifractal scaling, which is determining the nature of the asymptotic behavior of velocities, and whose parameter evaluation is therefore of great interest currently. We combine singular value decomposition techniques and wavelet transform analysis to generalize the multifractal formalism to vector-valued random fields. The so-called Tensorial Wavelet Transform Modulus Maxima (TWTMM) method is calibrated on synthetic self-similar 2D vector-valued multifractal measures and monofractal 3D vector-valued fractional Brownian fields. We report the results of some application of the TWTMM method to turbulent velocity and vorticity fields generated by direct numerical simulations of the incompressible Navier–Stokes equations. This study reveals the existence of an intimate relationship between the singularity spectra of these two vector fields which are found significantly more intermittent than previously estimated from longitudinal and transverse velocity increment statistics.

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Alain ArneodoEmail:

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