SIMPLE VALIDATORY TOOLS FOR JUDGING THE PREDICTIVE PERFORMANCE OF PARAFAC AND THREE-WAY PLS

The methods PARAFAC and three-way PLS are compared with respect to their ability to predictreversed-phase retention values.Special attention is paid to simple validatory tools,the meaning and useof which are explained.The simple validatory tools consist of percentages of explained variation in the training set and thosethat can be calculated with the use of markers.These markers are special(reference)solutes,the retentionvalues of which are used to gain information about a new object for which predictions are wanted.Different validatory tools can be calculated with the use of these marker retention values:percentagesof used variation and mean sum of squared residuals after applying the model to these marker retentionvalues.The validatory tools are evaluated on their power to estimate their test set counterparts:thepercentages of explained variation in the test set and mean sum of squared prediction errors in the test set.Two different data sets from reversed-phase chromatography are used to evaluate the validatory tools.The first data set has a high signal-to-noise ratio and is measured under the same measurementconditions.The second data set has a low signal-to-noise ratio and is measured under differentmeasurement conditions.Some of the simple validatory tools seem to have relevance to their test setcounterparts,even in the case of the second data set.     

An Exploration of Building a Thematic Sub-database within the Framework of DDE:A New Detrital Zircon U-Pb Dating Database

正Within the framework of the Deep-time Digital Earth (DDE)project,thematic databases driven by scientific issues will have strong scientific vitality.In the field of sedimentology,thematic databases based on the current unified sedimentary knowledge tree established by the Sedimentary Data Group (Fig.1),can solve specific scientific problems effectively and improve the scope and utility of the DDE platform significantly.     

A comparative study of boron isotopes and trace elements of the marine foraminifers during the last glacial maximum and Holocene

Boron isotopic compositions in marine planktonic foraminifers can record changes in seawater pH and hence provide a new tool to reconstruct the changes of paleo-atmospheric PCO2.Here a comparative study was done on boron isotopes and trace element abundances of planktonic foraminifers,Globigerinoides sacculifer and Globigerinoides ruber from three tropical ODP sites,Site 806B,Site 664C and Site 999A.It is demonstrated here that G.ruber is a better species to be used for downcore boron isotope analyses on gl...     

基于熵值-理想点法的泥石流危险度研究

泥石流危险度的划分是泥石流研究中的重点与难点,泥石流危险度的确定对于泥石流整体特征的把握具有十分重要的作用。采用熵值-理想点法建立了泥石流危险度划分模型,选取流域面积、主沟长度与泥石流沟相对最大高差等10个评价指标。利用现场3条泥石流沟作为工程评价对象,通过熵值法确定各评价指标的权重系数,并采用理想点法进行泥石流危险度的划分研究。根据模型分析结果,泥石流沟2与3属于高危险度(贴近度为0.79与0.83),泥石流沟1属于中危险度(贴近度为0.82)。泥石流危险度与现场情况及已有研究资料基本一致,证明了该法在泥石流危险度划分中的合理性与有效性。     

Seismic attenuation in Faroe Islands basalts

We analysed vertical seismic profiling (VSP) data from two boreholes at Glyvursnes and Vestmanna on the island of Streymoy, Faroe Islands, to determine the magnitude and causes of seismic attenuation in sequences of basalt flows. The work is part of SeiFaBa, a major project integrating data from vertical and offset VSP, surface seismic surveys, core samples and wireline log data from the two boreholes. Values of effective seismic quality factor (Q) obtained at Glyvursnes and Vestmanna are sufficiently low to significantly degrade the quality of a surface reflection seismic image. This observation is consistent with results from other VSP experiments in the North Atlantic region. We demonstrate that the most likely cause of the low values of effective Q at Glyvursnes and Vestmanna is a combination of 1D scattering and intrinsic attenuation due to seismic wave‐induced fluid flow within pores and micro‐cracks. Tests involving 3D elastic wave numerical modelling with a hypothetical basalt model based on field observations, indicate that little scattering attenuation is caused by lateral variations in basalt structure.     

稳定性层状云降雨量的估算研究

党的十六届五中全会明确提出了建设社会主义新农村。为充分发挥气象科技业务服务在新农村建设中的作用,使推进社会主义新农村建设的部署落到实处,按照中国气象局的要求,结合山西省实际情况,山西省气象局于2006年3月下旬进行了气象为建设社会主义新农村服务的调研活动。组织机构:成立了以山西省气象局党组书记、局长张世英为组长,副局长李韬光为副组长的新农村建设调研领导小组,从山西省气象局预测减灾与科技处、山西省气候中心等有关单位抽调了一批政治素质好,业务水平高的技术骨干组成了调研组。调研方法:主要通过问卷调研、专题调研、实地…     

Geological characterization of the Prestige sinking area

The tanker Prestige sank off NW Iberia on the 19th November 2002. The stern and bow of the Prestige wreck are located on the southwestern edge of the Galicia Bank, at 3565 m and 3830 m water depths, respectively. This bank is a structural high controlled by major faults with predominant N-S, NNE-SSW, and NNW-SEE trends. It is characterized by moderate to low seismic activity. The faults have controlled the local depositional architecture, deforming, fracturing, relocating and distributing sediments since the Valangian (early Cretaceous). The Prestige sinking area corresponds to an asymmetric half-graben structure with a N-S trend, which conditions the present-day morphology. The faulted flank outcrops and its activity and erosion have favoured the occurrence of mass-movements (slumps, slump debris, mass-flows and turbidity currents), building valleys and depositional lobes. Nearsurface sediments comprise mostly terrigenous and biogenous turbiditic muds and sands with a minor presence of hemipelagic muds, except on the fault scarp where pelagites predominate. Potential geological hazards resulting from tectonic and sedimentary processes affect almost the entire Prestige sinking area.