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Zhengyong REN Jingtian TANG Feiyan WANG Xiao XIAO Changsheng LIU Rongwen GUO 《Frontiers of Earth Science》2010,4(2):229-236
In this paper, we introduced a clear object-oriented framework to implement the complicated adaptive procedure with C ++ programming
language. In this framework, it consisted of the unstructured mesh generation, a-posterior error estimating, adaptive strategy,
and the postprocessing. Unlike the procedure-oriented framework, which is commonly used in DC resistivity modeling with FORTRAN
language, the object-oriented one, which is famous for its characteristic of encapsulation, could be used for a class of problems
that would be executed by only making some changes on the user interface. To validate its flexibility, two synthetic DC examples
were tested here. 相似文献
33.
Phosphorus distribution in the sediments of a shallow eutrophic lake,Lake Chaohu,China 总被引:8,自引:5,他引:3
Fengyu Zan Shouliang Huo Beidou Xi Qingqin Li Haiqing Liao Jingtian Zhang 《Environmental Earth Sciences》2011,62(8):1643-1653
In this study, the sediment profiles of total phosphorus (TP), inorganic phosphorus (Pi), organic phosphorus (Po), C/P and N/P were used to investigate time-dependent P distribution changes in Lake Chaohu. The characteristics of Pi and Po fractions in the surface sediments were studied and the difference between east and west lake region was also discussed.
The Pi and Po contents displayed a clear gradient from east to west in sediments of Lake Chaohu, and the Po/P ratios were lower in sediments with industrial and urban pollution sources input in west lake region. The study indicated
that different sediments area had diverse concentrations and distributions of Po fractions due to their different drainage basin and pollution sources. The profile distribution of the C/P and N/P ratios
decreased with increasing depths and stayed relatively constant ratios at the depths of 15–30 cm. The C/P and N/P ratios were
always below Redfield ratios in sediment profile, indicating P enrichment but likely due to the preferential loss of carbon
in respect to phosphorus. The rank order of Pi-fractions extracted was HCl-Pi > NaOH-Pi > NaHCO3-Pi in surface sediments. The relative distribution of NaHCO3-Pi and HCl-Pi was in agreement with the trophic conditions of the regions studied. Among the sequentially extracted Po forms, the rank order of Po fractions was residual Po > HCl-Po > fulvic acid-P > humic acid-P > NaHCO3-Po, with mean relative proportion of 5.4:3.4:2.2:1.1:1.0. 相似文献
34.
利用长期观测数据结合预测模型对大坝的形变趋势进行估计评价是大坝结构安全监测的必要内容。本文综合利用EMD和RBF神经网络,研究大坝变形时间序列中非线性周期信号变化的内在规律,使用西龙池L022号站4000期数据作为训练样本,对后续80期数据进行预测,并通过对预测结果与实测变形差值的统计分析评价本文方法的预测水平。结果表明,N、E、U 3个方向的RMSE分别为0.878 6、0.360 4和2.235 mm。与BP进行对比,RBF预测效果更好,受数据精度影响较小,MAE、RMSE较BP分别最高可提高63%、57%,且本文方法计算效率高,泛化能力强。 相似文献
35.
Yao Hongbo Ren Zhengyong Tang Jingtian Lin Yufeng Yin Changchun Hu Xiangyun Huang Qinghua Zhang Keke 《中国科学:地球科学(英文版)》2021,64(10):1798-1812
Science China Earth Sciences - The accumulated large amount of satellite magnetic data strengthen our capability of resolving the electrical conductivity of Earth’s mantle. To invert these... 相似文献
37.
水平多层介质上水平电偶源频率电磁测深的阻抗实部等效电阻率 总被引:3,自引:0,他引:3
本文讨论了水平电偶源频率电磁测深中阻抗实部等效电阻率的具体定义和算法。用该方法计算的等效电阻率是电磁响应的单值函数,并极大地改善了视电阻率随频率变化的关系曲线,能直观地反映出地电断面随深度的客观变化,数值较接近地层真电阻率,且接近速度很快,假极值效应明显压低。数值计算和实际应用表明该方法是灵活、可行的,可很好地消除频率电磁测深中波区视电阻率曲线在非波区的畸变效应。 相似文献
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AI Bo YU Mengchao GUO Jingtian ZHANG Wei JIANG Tao LIU Aichao WEN Lianjie LI Wenbo 《中国海洋大学学报(英文版)》2022,21(2):277-290
Numerical models and correct predictions are important for marine forecasting,but the forecasting results are often unable to satisfy the requirements of operational wave forecasting.Because bias between the predictions of numerical models and the actual sea state has been observed,predictions can only be released after correction by forecasters.This paper proposes a spati-otemporal interactive processing bias correction method to correct numerical prediction fields applied to the production and release of operational ocean wave forecasting products.The proposed method combines the advantages of numerical models and Forecast Discussion;specifically,it integrates subjective and objective information to achieve interactive spatiotemporal correc-tions for numerical prediction.The method corrects the single-time numerical prediction field in space by spatial interpolation and sub-zone numerical analyses using numerical model grid data in combination with real-time observations and the artificial judg-ment of forecasters to achieve numerical prediction accuracy.The difference between the original numerical prediction field and the spatial correction field is interpolated to an adjacent time series by successive correction analysis,thereby achieving highly efficient correction for multi-time forecasting fields.In this paper,the significant wave height forecasts from the European Centre for Medium-Range Weather Forecasts are used as background field for forecasting correction and analysis.Results indicate that the proposed method has good application potential for the bias correction of numerical predictions under different sea states.The method takes into account spatial correlations for the numerical prediction field and the time series development of the numerical model to correct numerical predictions efficiently. 相似文献