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101.
Rainfall modeling is one of the major component process in the meteorological engineering. Hence, exploring an advance and reliable intelligent model for its forecasting is essential for water resources engineering. In this current research, novel integrative intelligence model coupled with phase space reconstruction is proposed to forecast monthly rainfall in Chhattisgarh State, India. The proposed model is a hybridization of support vector machine (SVM) model with firefly optimization algorithm (FFA). The modeling is undertaken based on three stages starting with configuring the delay time and embedding dimension using mutual information and false nearest neighbors to determine the input matrix of the forecasting model. In the second stage, the firefly optimizer is employed to tune the SVM model. Finally, the hybrid model is conducted to forecast the monthly time scale rainfall time series. Monthly time scale rainfall data for sixteen raingauge stations over a century (1901–2002) are utilized and tested. A validation of the capacity of the suggested model is carried out by comparing the accuracy results with classical SVM and hybrid SVM-FFA “without mutual information analysis” models. The three predictive models are trained using 75% of available data set and tested the remaining 25% dataset. The model’s results were statistically verified using mean absolute error and best-good-fitness measurements in addition to Taylor diagram visualization. In conclusion, the proposed model was significantly improved the forecasting accuracy of the modeling. Also, it was exhibited a very robust intelligent model that can be applied for the Indian regional zone for monthly rainfall forecasting.  相似文献   
102.
Water Resources Management - Accurate water level forecasting is important to understand and provide an early warning of flood risk and discharge. It is also crucial for many plants and animal...  相似文献   
103.
Radiation‐induced graft polymerization of low‐density polyethylene with N‐vinylpyrrolidone, LDPE‐g‐PNVP, was used as a starting material for the synthesis of polyfunctionally substituted heterocyclic products. Thus, LDPE‐g‐PNVP reacts with ylidenemalononitrile derivatives to give the Michael addition products. In multistep reaction, LDPE‐g‐PNVP reacts with N,N‐dimethylformamide dimethyl acetal (DMFDMA), hydrazine hydrate and malononitrile, respectively, to give a hydropyrrolopyridazine derivative. The latter could also be prepared via the reaction of LDPE‐g‐PNVP with DMFDMA, followed by treating with cyanoacetohydrazide. Also, LDPE‐g‐PNVP reacts with malononitrile to give an adduct product, dimer malononitrile derivative 13. The latter reacts with sulfur element to afford the thiophene derivative. Furthermore, this adduct reacts with hydrazine hydrate to isolate the original starting material, LDPE‐g‐PNVP, and aminopyridine derivative. The resulted films were characterized by infrared (IR) spectroscopy, 1H nuclear magnetic resonance (1H‐NMR) mass spectroscopy, elemental analysis, swelling behavior, and electron scanning microscope. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2963–2970, 1999  相似文献   
104.
Multimedia Tools and Applications - According to the World Health Organization, Coronary Artery Disease (CAD) is a leading cause of death globally. CAD is categorized into three types, namely...  相似文献   
105.
Engineering with Computers - A substantial number of experimental studies have reported on the flexural performance of concrete-filled steel tube (CFST) beams. Due to the problem complexity,...  相似文献   
106.
Microsystem Technologies - In the original article, one of the co-author’s (Ghader Rezazadeh) surname has been published incorrectly. The correct surname should be Rezazadeh.  相似文献   
107.
S. Hawash  F. Zaher  O. Kenawi 《Fuel》2009,88(3):579-582
Transesterification of Jatropha oil using supercritical methanol and in absence of a catalyst has been studied under different conditions of temperature (from 512 to 613 K), pressure (from 5.7 to 8.6 MPa) and molar ratio of alcohol to oil (from 10 to 43 mol alcohol per mol oil). The reaction products were analyzed for their content of residual triglycerides, glycerol, monoglycerides, diglycerides, esters and free acids by high performance liquid chromatography (HPLC), thin layer chromatography (TLC) and titration against KOH.The results have revealed that 100% yield of esters can be obtained using super critical methanol within four min only, at a temperature of 593 K and under a pressure of 8.4 MPa pressure. The molar ratio of methanol to oil was 43:1.  相似文献   
108.
The low-energy muon facility at PSI provides nearly fully polarized positive muons with tunable energies in the ke V range to carry out muon spin rotation(LE-μSR)experiments with nanometer depth resolution on thin films,heterostructures, and near-surface regions. The low-energy muon beam is focused and transported to the sample by electrostatic lenses. In order to achieve a minimum beam spot size at the sample position and to enable the steering of the beam in the horizontal and vertical direction, a special electrostatic device has been implemented close to the sample position. It consists of a cylinder at ground potential followed by four conically shaped electrodes,which can be operated at different electric potential. In LE-μSR experiments, an electric field at the sample along the beam direction can be applied to accelerate/decelerate muons to different energies(0.5–30 keV). Additionally, a horizontal or vertical magnetic field can be superimposed for transverse or longitudinal field μSR experiments. The focusing properties of the conical lens in the presence of these additional electric and magnetic fields have been investigated and optimized by Geant4 simulations. Some experimental tests were also performed and show that the simulation well describes the experimental setup.  相似文献   
109.
110.
Water Resources Management - Geographic Information System (GIS) are an intelligence technique skilled to extract, store, manage and display the spatial information for various applications of...  相似文献   
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