Parametric study of molecular line polarization in the solar atmosphere     

K. E. Rangarajan  D. Mohan Rao 《Journal of Astrophysics and Astronomy》2000,21(3-4):269-269

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Application of soft computing techniques for shallow foundation reliability in geotechnical engineering     

Rahul Ray  Deepak Kumar  Pijush Samui  Lal Bahadur Roy  A.T.C.Goh  Wengang Zhang 《地学前缘(英文版)》2021,12(1):375-383

This research focuses on the application of three soft computing techniques including Minimax Probability Machine Regression(MPMR),Particle Swarm Optimization based Artificial Neural Network(ANN-PSO)and Particle Swarm Optimization based Adaptive Network Fuzzy Inference System(ANFIS-PSO)to study the shallow foundation reliability based on settlement criteria.Soil is a heterogeneous medium and the involvement of its attributes for geotechnical behaviour in soil-foundation system makes the prediction of settlement of shallow a complex engineering problem.This study explores the feasibility of soft computing techniques against the deterministic approach.The settlement of shallow foundation depends on the parametersγ(unit weight),e0(void ratio)and CC(compression index).These soil parameters are taken as input variables while the settlement of shallow foundation as output.To assess the performance of models,different performance indices i.e.RMSE,VAF,R^2,Bias Factor,MAPE,LMI,U(95),RSR,NS,RPD,etc.were used.From the analysis of results,it was found that MPMR model outperformed PSO-ANFIS and PSO-ANN.Therefore,MPMR can be used as a reliable soft computing technique for non-linear problems for settlement of shallow foundations on soils.  相似文献   

Correction to: Projection of Iron Ore Production     

Mohr  Steve  Giurco  Damien  Yellishetty  Mohan  Ward  James  Mudd  Gavin 《Natural Resources Research》2020,29(1):561-561

Natural Resources Research - The original version of this article unfortunately contained an error in Equation 3.  相似文献   

生态遥感新锐——轻小型无人机的应用     

张菁  孙千惠  叶震  杨默含  赵晓霞  巨袁臻  胡天宇  郭庆华 《热带地理》2019,39(4):604-615

基于研究对象视角梳理轻小型无人机遥感手段在生态学研究中的应用现状，重点分析了无人机在不同生态对象应用的优势和局限：优势主要在于其能够高灵活性、高分辨率地获取各生态对象的数据，为较大规模的生态研究提供了便利。在农田生态系统应用中主要关注农田信息检测、自动化农作等方面，但在这方面的应用还比较单一，缺乏更深层更全面的系统化应用；在森林草地中主要关注植被结构参数提取、生物量反演等，在数据采集过程中应注意设备的稳定性避免对数据准确性造成影响；城市生态系统主要集中在城市环境监测和测绘方面，同时城市方面飞控政策尚待完善；水生生态系统主要关注水生动植物监测和潮间带观测等，大规模监测也对设备续航和数据标准化处理提出了要求；动物研究应用中主要关注动物迁徙规律、物种分布等方面，在监测过程中需注意不要对动物栖息造成干扰。总的来说，无人机应用局限主要在于其获取的数据处理尚未标准化，飞控政策尚未成熟和硬件续航等方面。在此基础上探讨了未来无人机遥感在生态学研究的应用趋势：随着无人机智能化的软硬件发展和云端生态大数据的建立，无人机数据的获取和处理将更加智慧化，多源的无人机遥感数据将会更好地服务于生态学研究。  相似文献   

Erratum to: Hybrid attenuation model for estimation of peak ground accelerations in the Kutch region, India     

A. Joshi  Ashvini Kumar  K. Mohan  B. K. Rastogi 《Natural Hazards》2014,70(1):973-974

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Spectroscopic diagnostics for N III ion     

B. N. Dwivedi  Anita Mohan  A. K. Gupta 《Astrophysics and Space Science》1996,243(1):163-163

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Line diagnostics for Ne V and Mg V solar ions     

B. N. Dwivedi  Anita Mohan 《Solar physics》1995,158(2):237-248

Spectroscopic diagnostics for the Nev and Mgv solar ions have been investigated. The theoretical forbidden line ratios from these ions are presented for estimating the Ne/Mg variation in different solar structures. Calculations for density and temperature line diagnostics of these ions are given for the several spectral line ratios and their applications are discussed with the help of available solar observations in space. Future observations from the CDS and the SUMER experiments aboard the SOHO satellite are also discussed.  相似文献   

Study of thermal properties of supraglacial debris and degree-day factors on Lirung Glacier,Nepal     

Mohan Bahadur Chand  Rijan Bhakta Kayastha 《寒旱区科学》2018,10(5):357-368

The extensive debris that covers glaciers in the ablation zone of the Himalayan region plays an important part in regulating ablation rates and water availability for the downstream region. The melt rate of ice is determined by the amount of heat conducted through debris material lying over the ice. This study presents the vertical temperature gradients, thermal properties in terms of thermal diffusivity and thermal conductivity, and positive degree-day factors for the debris-covered portion of Lirung Glacier in Langtang Valley, Nepal Himalaya using field-based measurements from three different seasons.Field measurements include debris temperatures at different debris thicknesses, air temperature, and ice melt during the monsoon(2013), winter(2013), and pre-monsoon(2014) seasons. We used a thermal equation to estimate thermal diffusivity and thermal conductivity, and degree-day factors(DDF) were calculated from cumulative positive temperature and ice melt of the measurement period. Our analysis of debris temperature profiles at different depths of debris show the daily linear gradients of-20.81 °C/m, 4.05 °C/m, and-7.79 °C/m in the monsoon, winter, and pre-monsoon seasons, respectively. The values of thermal diffusivity and thermal conductivity in the monsoon season were 10 times greater than in the winter season. The large difference in these values is attributed to surface temperature and moisture content within the debris. Similarly, we found higher values of DDFs at thinner debris for the pre-monsoon season than in the monsoon season although we observed less melting during the pre-monsoon season. This is attributed to higher cumulative temperature during the monsoon season than in the pre-monsoon season. Our study advances our understanding of heat conductivity through debris material in different seasons, which supports estimating ice melt and discharge from glacierized river basins with debris-covered glaciers in the Himalayan region.  相似文献   

Critical evaluation and geological correlation of teleseismic phase data from Indian seismological stations     

G Mohan  S S Rai 《Journal of Earth System Science》1992,101(4):387-401

We evaluated the quality of seismic phase data from Indian seismological stations through the analysis of teleseismic travel times reported during 1976–83 and infer that only WWSSN stations (NDI, SHL, POO, KOD) apart from GBA and HYB can be rated satisfactory while the majority of stations (more than 40) produce very poor quality data sets. Detailed analysis of teleseismic P-wave travel time residuals shows that while the average structure of the upper mantle beneath India has high velocity (negative residuals) there are marked lateral variations. In particular, three zones of anomalous positive residuals (low velocity) are observed: one beneath the north western part of the Deccan trap, the second covering the southernmost peninsula (granulite terrain) and a third rather localized one, to the north of Delhi coinciding with Delhi-Haridwar ridge. New Delhi exhibits strong negative residuals in the E-SE quadrant along with negative station anomaly, implying that it is underlain by an anomalous high velocity crust/upper mantle. The negative residuals observed over India, continue beneath the Himalaya till the south of Lhasa but change sign further northward, suggesting the northern limit of the Indian upper mantle structure.  相似文献   

Use of the Hilbert transform to interpret self-potential anomalies due to two-dimensional inclined sheets     

N. Sundararajan  I. Arun Kumar  N. L. Mohan  S. V. Seshagiri Rao 《Pure and Applied Geophysics》1990,133(1):117-126

Self-potential anomalies due to two-dimensional inclined sheet of finite depth extent are analysed from their horizontal and vertical derivatives via the Hilbert transform. The depths to the top and bottom of the sheet and the inclination are obtained by means of simple mathematical expressions. The method is applied to a theoretical example and to a field S.P. anomaly over a sulphide deposit in the Kalava fault zone of Cuddapah basin, India. The presence of random noise is analysed for various levels and its effect is discussed. This interpretation process can be automated for all practical purposes by simple programming.  相似文献