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971.
This article is based on experiences with data and text mining to gain information for strategic business decisions, using host-based analysis and visualisation (A/V), primarily in the field of patents. The potential advantages of host-based A/V are pointed out and the features of the first such A/V software, STN®AnaVist™, are described in detail. Areas covered include the user interfaces, initial set of documents for A/V, data mining, text mining, reporting, and suggestions for further development. 相似文献
972.
P. Farzadi 《Journal of Petroleum Geology》2006,29(2):159-173
Interpretation of recently acquired 3D seismic data from the adjacent Sirri C and D oilfields in the SE Persian Gulf indicates that a 3D interpretation of seismic facies is crucial to resolve the internal stratal geometries of the Aptian Dariyan Formation. This carbonate formation passes southward into the Shu'aiba Formation, a prolific reservoir rock of similar facies in the UAE. Lack of exposures and limited cored intervals have forced reliance on the seismic data for evidence of the depositional environment and the internal architecture of potential reservoir rocks. The progradational nature of the Dariyan Formation and the occurrence of carbonate build‐ups within it make this stratal geometry complex. The complex internal heterogeneity of the build‐ups and presence of seismic noise make mapping of the build‐ups in 3D space using conventional seismic interpretation tools difficult, despite the availability of high‐quality 3D seismic data covering the area. The high quality seismic and limited well data from this field is one of the few datasets of this kind presented in the literature. A procedure for the hierarchical multi‐attribute analysis of seismic facies using Paradigm's Seis Facies software is used in this study to provide a 3D interpretation of the stratal patterns. Principal component analysis reduces the noise and redundant data by representing the main data variances as a few vector components in a transformed coordinate system. Cluster analysis is performed using those components which have the greatest contribution to the maximum spread of the data variability. Six seismic attribute volumes are used in this study and the result is a single 3D classified volume. Important new information obtained from within the Dariyan Formation gives new insights into its stratigraphic distribution and internal variability. This method of processing seismic data is a step towards exploring for subtle stratigraphic traps in the study area, and may help to identify exploration targets. 相似文献
973.
The existing geochemical diversity of clay deposits consists the underlying assumption for the determination of provenance of archaeological ceramics on the basis of their chemical composition. This assumption was tested on Quarternary red clayey alluviums from Central and Eastern Crete (Greece), an area rich in archaeological pottery and very popular for ceramics provenance studies. This type of clay has been used for pottery production on the island since the antiquity and it is still in use by traditional workshops. Altogether, 17 samples of clayey raw materials were collected from 7 different locations in Central and Eastern Crete, and characterised by chemistry, mineralogy and petrography. The study was focussed on the internal variability within deposits and the diversity among different deposits.It was possible to distinguish all seven deposits from each other on the basis of their chemical composition, taking into account the available mineralogical and petrographical information, although some deposits presented compositional relations. Compared to Neogene clay deposits in the same area, the variability among the examined red clayey deposits was clearly higher and exceeded by far the intra-deposit variability. 相似文献
974.
本文提出了用有限元法验证变幅杆解析法设计的可靠性,对三种类型的变幅杆先作解析法设计;然后利用有限元分析软件ANSYS进行模态分析,确定了变幅杆的固有频率,计算了固有频率与工作频率之间的相对误差,以此来评价解析法设计的可靠性;并分析了影响解析法设计可靠性的两个基本因素。 相似文献
975.
976.
为产生伪随机编码雷达波形,提高雷达低截获概率(LIP)和电子反干扰(ECCM)性能。针对logistic、full logistic、Kent三类最具代表性的映射所产生的混沌序列,在大量仿真基础上,对由此三类混沌序列获得的二相码相关性、平衡性及游程性等性能进行了比较分析,并给出了相应的仿真结果。研究表明三类混沌序列,都具有较好的伪随机特性,由此均可获得产生雷达波形的理性混沌二相码,Kent序列和full logistic序列的综合性能较好。 相似文献
977.
总结了中外学者对冲积性河流横断面形态调整规律研究的现状,从研究方法上对其进行归纳和分析。内容涉及到经验公式、终极假说和力学理论分析等相关领域,分析了横断面形态与水沙及河床边界条件的相关关系。并对渭河下游河道的横断面情况作了简要分析,建立了主槽河宽与水沙及河床前期边界条件的相关关系。最后总结了三种方法的特点,并对以后研究工作提出建议。 相似文献
978.
979.
Maha N Hajmeer Imad A Basheer Dean O Cliver 《Journal of the science of food and agriculture》2006,86(14):2337-2344
Reliability analysis is especially important when critical decisions are to be made involving potentially severe adverse consequences such as foodborne illness. Owing to uncertainty associated with the parameters controlling survival of Listeria monocytogenes in chorizo (a Mexican‐style sausage), the time needed to reduce the count by a certain number (n) of logs (tnD) is probabilistic. In this paper the first‐order second‐moment (FOSM) method based on Taylor series expansion is used to derive the expected value and standard deviation of tnD as function of the operating conditions (random variables) affecting survival, namely initial water activity (aw0) of the sausage batter, storage temperature (T) and airflow velocity (F), along with their uncertainties characterised by their means and coefficients of variation. For any given n the derived tnD probability distribution enables one to determine an estimate of tnD for any desired level of reliability or confidence level, such as 50% (median value), 95%, 99%, etc. Among the conclusions drawn were: (i) the variability associated with T and F has a minor effect on estimating uncertainty in tnD, whereas the reliability of tnD estimation is greatly influenced by the uncertainty in aw0; and (ii) the uncertainty in aw0 has the greatest impact when aw0 of the sausage formulation exceeds 0.90. The approach used and discussed in this paper can be applied to any survival/inactivation study to incorporate the effect of uncertainty in the various extrinsic and intrinsic parameters on the survival kinetics of the pathogen in a food system under evaluation. Copyright © 2006 Society of Chemical Industry 相似文献
980.
详细论述了南冲高架桥 6-2桩的检测过程 ,说明了岩溶地质对桩基质量的影响 ,并对此影响和预防措施进行了论述 相似文献