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81.
Hosseini-Dinani Hengameh Mokhtari Ahmad Reza Shahrestani Shahed De Vivo Benedetto 《Natural Resources Research》2019,28(3):967-994
Natural Resources Research - A variety of factors contribute to the proper and efficient evaluation of geochemical programs including sampling medium, sample size and sample fraction, sampling... 相似文献
82.
Zekri Hamid Cohen David R. Mokhtari Ahmad Reza Esmaeili Abbas 《Natural Resources Research》2019,28(3):867-868
Natural Resources Research - The original version of this article unfortunately contained a mistake in the second part of Table 3. The data in last four rows of Table 3, i.e.,... 相似文献
83.
Turner-McGrievy Gabrielle Karami Amir Monroe Courtney Brandt Heather M. 《Natural Hazards》2020,103(1):1035-1049
Natural Hazards - Little is known about what foods/beverages (F&B) are common during natural disasters. The goal of this study was to track high-frequency F&B mentions during four... 相似文献
84.
Acta Geotechnica - Dry granular materials have been the subject of many investigations, while wet granular materials, which widely exist in many real-world applications, have only received limited... 相似文献
85.
Spatial Modeling of Geotechnical Information Using GML 总被引:1,自引:0,他引:1
Geotechnical data characterizes the geometry and physical properties of soil deposits, which are determined from field observations, in-situ and laboratory tests, and engineering analyses. Until now, geotechnical information was mainly described and exchanged as relational data, which occasionally included spatial characteristics. Hereafter, the spatial features of geotechnical data are investigated by invoking the geotechnical data model of the Association of Geotechnical and Geoenvironmental Specialists (AGS), which is widely used in the United Kingdom to exchange geotechnical data in engineering practice. The basic geometric objects in AGS geotechnical data are first identified. These geometric objects are mapped to basic geometric features of the Geography Markup Language (GML). AGS data can therefore be fully rendered using GML-conformant schemas, which make geotechnical data readily importable into GML-aware applications. The data can be also imported to mainstream GIS applications using Extensible Markup Language (XML) transformations. This article demonstrates the rendition of AGS data format to a GML-conformant schema and illustrates the implementation of the new format through a few geotechnical examples. 相似文献
86.
The design of fixed or floating offshore structures requires accurate information of the met-ocean data at the intended offshore site. In the design process it is recognized that this environmental data is modified in the near-field by the interaction with the particular geometrical configuration of the offshore structure. This transformation of the incident wave field around and beneath an offshore structure presents a challenge for ocean engineers when specifying the wave gap elevation to avoid impact loads on the underside of the deck and inundation of the topsides. Thus, the accurate estimation of the wave crest distributions from measurements at various locations near and under the offshore structure during model test studies is essential. A semi-empirical approach is presented herein that builds upon the findings of previous studies and introduces the Method of L-moments. A three parameter model for a wave crest probability distribution function is presented and explicit relationships between the parameters of the distribution and its’ first three L-Moments are established. Furthermore, three narrow-band models from earlier research studies are reviewed and compared with the new model. Wave measurements from a mini-TLP model test program are used as the basis for comparison of the four distributions. The root-mean-square error is used as a metric to quantify the overall fit of the data and its accuracy in the high end tail of the data. The L-Moment model is shown to be more robust in representing the data in both the far-field and beneath the deck of the mini-TLP where the wave field demonstrates increased non-linear behavior. 相似文献
87.
The transmission and reduction of vibrations in the far-field of the surface of the ground due to a surface load is investigated theoretically and validated with given field measurement data. The performance of a given stabilization column, located directly underneath the load, at a number of receiver positions is studied and measured in terms of insertion loss. A numerical model is presented, which enables the wave-field in the region of the column to be determined, based on an integral equation formulation of the problem which is solved using a boundary element approach. It is shown that the column has a beneficial effect at low frequencies especially in certain frequency bandwidths and is validated with field data. However, when the Rayleigh wavelength becomes short compared with the depth and width of the column adverse effects occur at some frequencies which are also observed in the far-field. Various depths of columns and material properties of the surrounding soil medium are studied and results presented so that some preliminary physical conclusions may be derived. 相似文献
88.
Vertical eddy diffusivity estimations in Swan river estuary 总被引:1,自引:0,他引:1
A field experiment is described in which diapycnal diffusivity is estimated by direct and indirect methods in Swan river estuary, Perth, Western Australia. The microstructure profiles were collected in a narrow and straight part of this estuary using a portable flux profiler (PFP). The profiles were segmented into stationary parts and the rate of vertical eddy diffusivity was estimated for the segments within the pycnocline. The direct measurement showed that instantaneous flux could be positive or negative with a low net rate of vertical eddy diffusivity for mass of about 6.5 × 10−8 m2 s−1. All the indirect methods overestimated this rate. However, within the indirect methods, the method of Osborn yielded the poorest estimate while the method of Osborn and Cox gave the closest estimate. 相似文献
89.
90.
Amir Aabbas Katebi Ali Khojasteh Mohammad Rahimian Ronald Y. S. Pak 《国际地质力学数值与分析法杂志》2010,34(12):1211-1236
A theoretical formulation is presented for the determination of the interaction of a vertically loaded disc embedded in a transversely isotropic half‐space. By means of a complete representation using a displacement potential, it is shown that the governing equations of motion for this class of problems can be uncoupled into a fourth‐order partial differential equation. With the aid of Hankel transforms, a relaxed treatment of the mixed‐boundary value problem is formulated as dual integral equations, which, in turn, are reduced to a Fredholm equation of the second kind. In addition to furnishing a unified view of existing solutions for zero and infinite embedments, the present treatment reveals a severe boundary‐layer phenomenon, which is apt to be of interest to this class of problems in general. The present solutions are analytically in exact agreement with the existing solutions for a half‐space with isotropic material properties. To confirm the accuracy of the numerical evaluation of the integrals involved, numerical results are included for cases of different degrees of the material anisotropy and compared with existing solutions. Further numerical examples are also presented to elucidate the influence of the degree of the material anisotropy on the response. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献