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41.
Forecasting of space–time groundwater level is important for sparsely monitored regions. Time series analysis using soft computing tools is powerful in temporal data analysis. Classical geostatistical methods provide the best estimates of spatial data. In the present work a hybrid framework for space–time groundwater level forecasting is proposed by combining a soft computing tool and a geostatistical model. Three time series forecasting models: artificial neural network, least square support vector machine and genetic programming (GP), are individually combined with the geostatistical ordinary kriging model. The experimental variogram thus obtained fits a linear combination of a nugget effect model and a power model. The efficacy of the space–time models was decided on both visual interpretation (spatial maps) and calculated error statistics. It was found that the GP–kriging space–time model gave the most satisfactory results in terms of average absolute relative error, root mean square error, normalized mean bias error and normalized root mean square error. 相似文献
42.
The clumped isotope composition of carbonates provides a new way to retrieve temperatures for ancient geological systems without knowing the isotopic compositions of co‐existing fluid/minerals. The application of this new thermometer in the past decade, however, has been largely restricted to low‐temperature (<~250 °C) geological processes. In this study, we present clumped isotope analyses for marbles collected from the Backbone Range of Taiwan, which has been subjected to greenschist facies metamorphism during the ongoing arc–continent collision. We find that the ∆47 temperatures either indicate temperatures of the last dynamic open‐system recrystallization of marbles due to tectonic movement/stress or signify closed‐system closure temperatures during rock exhumation, demonstrating that clumped information from marbles has great potential for revealing process characteristics during mountain building. 相似文献
43.
S. Siddiqui K. Otaif M. Asaduddin Laskar 《International Journal of Environmental Science and Technology》2016,13(12):2951-2960
The presence of heavy metals in diverse forms in the environment (which is having a direct and continuous interface with the health of living beings) demands an efficient removal technique which would be cost effective, eco-friendly, easily operable and free of secondary waste. Hence, the useless and discarded leaves of Cissus rotundifolia have been valorized by utilizing it for the removal of heavy metal pollutant after its modification. The developed adsorbent is then characterized through X-ray diffraction study, scanning electron microscope analysis, Fourier transform infrared spectroscopy and application of mathematical models. The adsorption process was found to follow Langmuir isotherm model and pseudo-first-order kinetics. The intraparticle diffusion was found to be the rate limiting step. Besides being usable in batch method, this adsorbent is also applicable to fixed bed column technique, due to its faster kinetics, high hydrophilicity, and easy recovery with mild mineral acid (like 0.002 mol per liter of hydrochloric acid). 相似文献
44.
Mostafizur Rahaman Laskar Suman Chatterjee Aniruddha Das 《Journal of the Indian Society of Remote Sensing》2018,46(6):873-883
Air pollution is a major problem, conscious both for health and surroundings. This is a novel approach for the design & development of a system for the monitoring of different air pollutants especially at remote places where it is difficult to install any conventional air quality monitoring stations as well as for the cities. In this research work, a framework of Functional air quality index which is an indicator of susceptibility to respiratory illness has been built using the Bayesian neural network to provide the random real-time data about a location through wireless communication. The monitoring system is integrated with different types of sensors to measure the level of different air pollutants or air quality parameters such as Suspended particulate matters, (PM2.5), Nitrogen dioxide, Sulphur dioxide, Ozone which are directly associated with airways inflammatory diseases such as Asthma, Bronchitis, COPD. Each location in Map (GPS) can be updated automatically with fAQI to the user through mobile computing and satellite commutation. The user gets information about the neighborhood location with health-related information such as- whether a particular location is sensitive to respiratory diseases such as Bronchitis, asthma, COPD etc. due to suspended allergen/pollutants in the ambient air. This novel approach is designed with its’ own prototype and an application of Inter of Things in Health GIS for the benefit of humanity. 相似文献
45.
Climate friction and the Earth's obliquity 总被引：1，自引：0，他引：1
46.
In the numerical integrations of the outer planets, when the inner planets are not considered, the initial conditions are determined by least square adjustment with a complete ephemeris. In the present work, we compute the resulting uncertainty on the initial conditions by the analysis of the very simple problem which consists in fitting by least squares a straight line to a sine curve. Explicit formulae for the computation of the error due to the fitting process are given. In particular, fitting over an integer number of periods is very close to the worst case. The determination of the initial conditions in the LONGSTOP project (Milani,et al., 1987) is analysed as an example. It is shown that the uncertainty on the main frequencies of the secular system due to the determination of the initial conditions is of the order of 0.01 arcsec/year. 相似文献