Hourly River Flow Forecasting: Application of Emotional Neural Network Versus Multiple Machine Learning Paradigms

Water Resources Management - Monitoring hourly river flows is indispensable for flood forecasting and disaster risk management. The objective of the present study is to develop a suite of hourly...     

Annual Rainfall Forecasting Using Hybrid Artificial Intelligence Model: Integration of Multilayer Perceptron with Whale Optimization Algorithm

Water Resources Management - Rainfall, as one of the key components of hydrological cycle, plays an undeniable role for accurate modelling of other hydrological components. Therefore, a precise...     

Concrete corrosion in wastewater systems: Prediction and sensitivity analysis using advanced extreme learning machine

The implementation of novel machine learning models can contribute remarkably to simulating the degradation of concrete due to environmental factors. This study considers the sulfuric acid corrosive factor in wastewater systems to simulate concrete mass loss using five machine learning models. The models include three different types of extreme learning machines, including the standard, online sequential, and kernel extreme learning machines, in addition to the artificial neural network, classification and regression tree model, and statistical multiple linear regression model. The reported values of concrete mass loss for six different types of concrete are the target values of the machine learning models. The input variability was assessed based on two scenarios prior to the application of the predictive models. For the first assessment, the machine learning models were developed using all the available cement and concrete mixture input variables; the second assessment was conducted based on the gamma test approach, which is a sensitivity analysis technique. Subsequently, the sensitivity analysis of the most effective parameters for concrete corrosion was tested using three different approaches. The adopted methodology attained optimistic and reliable modeling results. The online sequential extreme learning machine model demonstrated superior performance over the other investigated models in predicting the concrete mass loss of different types of concrete.     

Development of optically transparent ZnS/poly(vinylpyrrolidone) nanocomposite films with high refractive indices and high Abbe numbers

A series of optically transparent ZnS‐poly(vinylpyrrolidone) (PVP) nanocomposite films with high refractive indices and high Abbe numbers have been prepared. Mercaptoethanol (ME) capped ZnS nanoparticles (NPs) were introduced into the PVP polymer matrix via simple blending with high nanophase contents. ME‐ZnS NPs of around 3 nm were prepared from zinc acetate and thiourea precursors in N,N‐dimethylformamide using ME as a capping agent. Transparent nanocomposite films with high refractive indices and high Abbe numbers can be easily prepared by a conventional film casting method. TGA results indicated that the ZnS/PVP nanocomposite films exhibit good thermal stability and the measured contents of ZnS NPs in the films agree well with the theoretical values. The refractive indices and the Abbe numbers of the ZnS/PVP nanocomposite films range from 1.5061 to 1.7523 and 55.6 to 20.4 with the content of ME‐ZnS NPs varied between 0 and 80 wt %, respectively. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Ligating behavior and metal uptake of N‐sulphonylpolyamine chelating resins anchored on polystyrene‐divinylbenzene beads

Amberlite XAD‐2 has been functionalized by coupling through –SO₂‐with ethylenediamine, propylenediamine, and diethylenetriamine to give the corresponding polyamine chelating resins I–III. The solid metallopolymer complexes of the synthesized chelating resins with Cu²⁺, Zn²⁺, Cd²⁺, and Pb²⁺ were synthesized. The polyamine derivatives and their metal complexes were characterized by elemental analysis, spectral (IR, UV/V, and ESR), and magnetic studies. The batch equilibrium method was utilized for using the chelating polyamines for the removal of Cu⁺², Zn⁺², Cd⁺², and Pb⁺² ions from aqueous solutions at different pH values and different shaking times at room temperature. The selective extraction of Cu⁺² from a mixture of the four metal ions and the metal capacities of the chelating resins were evaluated using atomic absorption spectroscopy. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1839–1846, 2005     

Copper complexes of some tetra- and pentapeptides containing polyfunctional amino acids

Copper complexes of some tetra- and pentapeptides [(I)-(VI)] containing lysine and ornithine are spectrophotometrically examined. It is shown that all tetra- and pentapeptides form red or reddish violet copper complexes with λ_max 515–540 nm, and copper-peptide ratio 1:1. The results achieved confirmed that the N⁶-amino group of the lysine residues or the N⁵-amino group of the ornithine residues do not participate in complex formation of tetra- and pentapeptides even when lysine or ornithine form the N-terminal amino acid in the peptide.     

Wind-powered electric water-pumping system installed in a remote location

In December 1996, the country's first wind-powered, electric water-pumping system was successfully installed at the Ministry of Water Resources (MWR) Heelat Ar Rakah Camp, a remote location some 900 kilometres south of Muscat, the capital city of Oman. A weather-monitoring station comprising temperature, wind speed/direction, humidity and barometric pressure equipment was also installed to investigate the relationship between weather conditions and power output. Both systems are still in operation and are providing valuable data for analysis. This paper investigates the pump's output at different wind speeds and monthly water output against average wind velocity and compares the results with the design output values provided by the system manufacturer. Problems encountered in meeting the irrigation requirements at the camp during periods of low wind are discussed and solutions proposed. The potential of utilizing surplus energy generated during periods of high wind is under investigation. The paper concludes by assessing and analysing the role of wind power amongst other renewable energy sources, in the abstraction and desalination of groundwater supplies.     

Interference mitigation and avoidance in uplink OFDMA with collaborative distributed intracell scheduling

A distributed collaborative uplink scheduling model in OFDMA systems is extended to a multicell scenario. On the intercell level, the scenarios with and without base station cooperation are investigated. In the cooperative case, base stations collaborate by performing pricing-based power control based on exchanging interference information. In the absence of intercell collaboration, probabilistic transmission is applied in each cell for interference avoidance. Simulations show that the proposed intercell interference mitigation and avoidance schemes lead to enhanced results.     

Preparation,characterization and dissolution behavior of artemisinin microparticles

In the present study, a modified 4-fluid nozzle spray drier was used to prepare microparticles of a poorly water soluble drug, artemisinin with the aim of improving its solubility. We also investigated the effect of process variables on the physical properties and dissolution rate of spray dried artemisinin. A full factorial experimentally designed study was performed to investigate the following spray drying variables: inlet temperature and feed concentration. The artemisinin powder and spray dried artemisinin microparticles were characterized by scanning electron microscopy (SEM), differential scanning calorimetric (DSC), X-ray diffraction (XRD) and dissolution. SEM study suggested that the inlet temperature and feed concentration impacted on the particle size of the spray dried particles. The crystallinity of spray dried particles was slightly decreased with increasing inlet temperature and concentration. The dissolution of spray dried particles was markedly improved as compared to commercial artemisinin. A dissolution surface-response model was used to elucidate the significant and direct relationships between drug feed concentration and inlet temperature on one hand and dissolution on the other hand. The best dissolution was found to be 117.00 ± 5.15 μg/mL at the drug feed concentration of 10 g/L and inlet temperature of 140 °C.     

Microwave-swing adsorption to capture and recover vapors from air streams with activated carbon fiber cloth

Adsorption with regeneration is a desirable means to control the emissions of organic vapors such as hazardous air pollutants (HAPs) and volatile organic compounds (VOCs) from air streams as it allows for capture, recovery, and reuse of those VOCs/HAPS. Integration of activated-carbon fiber-cloth (ACFC) adsorbent with microwave regeneration provides promise as a new adsorption/ regeneration technology. This research investigates the feasibility of using microwaves to regenerate ACFC as part of a process for capture and recovery of organic vapors from gas streams. A bench-scale fixed-bed microwave-swing adsorption (MSA) system was built and tested for adsorption of water vapor, methyl ethyl ketone (MEK), and tetrachloroethylene (PERC) from an airstream and then recovery of those vapors with microwave regeneration. The electromagnetic heating behavior of dry and vapor-saturated ACFC was also characterized. The MSA system successfully adsorbed organic vapors from the airstreams, allowed for rapid regeneration of the ACFC cartridge, and recovered the water and organic vapors as liquids.