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41.
Abstract

Coal is an important component in the energy industry and plays a key role in energy-producing facilities. Moisture is a common condition that has a considerable impact on coal. Coal drying has long been a question of great interest in a wide range of fields. Defining parameters in the coal drying is obtained by experiments. High costs, time constraints, and repetition of an experiment are one of the most frequently stated problems with experimental works. Using qualitative methods with experiments can be more useful for identifying and characterizing the coal drying process. The purpose of this article is finding the effective parameters in the coal drying process by using a hybridized prediction method. Genetic Algorithm (GA) and Artificial Neural Network (ANN) are hybridized with each other to identify and characterize the coal drying process. GA-ANN algorithm is applied to the coal drying process to predict the moisture of coal, but it does not provide a decent result at first. Later, the Design of Experiment (DoE) methodology is performed to determine the main effects of six parameters. Two scenarios are generated because two parameters are not statistically significant. The first scenario excludes the air relative humidity parameter, and the second scenario excludes the air relative humidity and the velocity of air parameters. Following the application of the DoE method, GA-ANN reaches decent results in scenario-2.  相似文献   
42.
The biological importance of Leu15 of epidermal growth factor(EGF) is suggested by its conservation through evolution, itscritical location in the domain–domain interface of EGFand its close proximity to Arg41, a residue that is crucialfor receptor binding and activation. Mutagenesis of Leu15 ofhuman EGF (hEGF) was employed to examine the role of this residuein the ligand-receptor interaction. The relative receptor affinitiesof the hEGF variants, as determined by radioreceptor competitionassays, varied depending on the amino acid substitution. TheL15F, L15W and L15V hEGF analogues had receptor affinities 45,26 and 18% respectively of wild type hEGF. The L15A and L15Ranalogues displayed receptor affinities of only 2.4 and 1.6%relative to wild type hEGF. No binding of the L15E analoguewas detected. The relative agonist activities, as measured byreceptor tyrosine kinase stimulation assays, generally followeda similar trend. The L15F, L15W and L15V analogues stimulatedthe receptor kinase to a level (Vmax) similar to that for wildtype hEGF. A striking difference was observed between the L15Aand L15R variants; although having similar binding affinities,the L15A mutant activated the receptor to only {small tilde}5%of the wild type Vmax in contrast to 53% for the L15R mutant1H-NMR analysis of the L15R and L15A mutants showed only minorstructural alterations that were not sufficient to account forthe dramatic losses in binding and agonist activities. The resultsindicate that both the size and hydrophobicity of the -branchedaliphatic side chain of Leu15 of hEGF are important in the formationof a catalytically active ligand–receptor complex.  相似文献   
43.
Support vector machines (SVM), a soft programming technique, has been used to estimate the temperature distribution and flow fields in a square porous enclosure heated discretely by three isothermal heaters from the left vertical wall. Right vertical wall of the cavity was isothermal but it has colder temperature than the heaters while remaining walls were adiabatic. A database was prepared by solving the governing equations which were written using Darcy flow model. Using finite difference method to discretize the equation, a computational fluid dynamics (CFD) code was written. A correlation was developed between Nusselt and Rayleigh numbers. Using obtained database, further values of temperature and velocities were estimated by SVM technique at different Rayleigh numbers and locations of heater. It was observed that SVM was a useful technique on estimation of streamlines and isotherms. Thus, SVM reduces the computational time and helps to solve some cases when CFD fails to solve due to numerical instability.  相似文献   
44.
Diker  Aykut  Sönmez  Yasin  Özyurt  Fatih  Avcı  Engin  Avcı  Derya 《Multimedia Tools and Applications》2021,80(16):24777-24800
Multimedia Tools and Applications - The accurate separation of ECG signals has become crucial to identify heart diseases. Machine learning methods are widely used to separate ECG signals. The aim...  相似文献   
45.
Interval type-2 fuzzy inverse controller design in nonlinear IMC structure   总被引:1,自引:0,他引:1  
In the recent years it has been demonstrated that type-2 fuzzy logic systems are more effective in modeling and control of complex nonlinear systems compared to type-1 fuzzy logic systems. An inverse controller based on type-2 fuzzy model can be proposed since inverse model controllers provide an efficient way to control nonlinear processes. Even though various fuzzy inversion methods have been devised for type-1 fuzzy logic systems up to now, there does not exist any method for type-2 fuzzy logic systems. In this study, a systematic method has been proposed to form the inverse of the interval type-2 Takagi-Sugeno fuzzy model based on a pure analytical method. The calculation of inverse model is done based on simple manipulations of the antecedent and consequence parts of the fuzzy model. Moreover, the type-2 fuzzy model and its inverse as the primary controller are embedded into a nonlinear internal model control structure to provide an effective and robust control performance. Finally, the proposed control scheme has been implemented on an experimental pH neutralization process where the beneficial sides are shown clearly.  相似文献   
46.
A new method of transient fault simulation uses dc bias grouping of faulty circuits and decreases the number of Newton-Raphson iterations needed to reach a solution. An experimental tool implementing this method achieves a speedup of 20% to 30% on a flat netlist.  相似文献   
47.
48.
The β-carotene degradation was investigated in carrot (Daucus carota L. cv Nantes) slices during convective drying at three temperatures (45, 55, and 65°C) at an airflow rate of 0.2 m s–1. Degradation kinetics of β-carotene in carrot slices during convective drying followed a first-order reaction. Drying temperature showed a significant effect on the degradation of β-carotene in carrot slices. The range of the reaction rate constants for β-carotene loses were 0.23 ± 0.08 –0.48 ± 0.04 h–1. The activation energy of β-carotene degradation is found 33.33 ± 0.05 kJ mol–1. Half-life time was calculated as 3.02 ± 0.04 h at 45°C, which dropped to 1.43 ± 0.03 h at 65°C.  相似文献   
49.
Ethylene diamine bisborane (EDB) was synthesized in a single step as the hydrogen storage material. The synthesized compound was firstly used in the literature for the production of hydrogen gas by catalytic hydrolysis reaction. Cu, Co and Ni nanoparticles with average sizes of 75–150 nm formed in p(acrylicacid-co-vinylimidazole) hydrogel network structures were used as catalysts for the hydrolysis reaction. The effect of the parameters such as catalyst type, EDB concentration, catalyst concentration, temperature and solvent environment on the catalytic hydrolysis reaction of EDB was investigated. In the activity tests for the catalyst, it was determined that the catalyst had a loss of only 15% in activity even at the end of 5 cycles. The activation energies of hydrolysis reaction were calculated as 39.42 kJmol–1, 44.77 kJmol–1 and 47.48 kJmol–1 for Cu, Co and Ni hydrogel composite catalyst, respectively.  相似文献   
50.
The air and oxy-fuel combustion processes of two low-grade lignite coals were investigated by thermogravimetric analysis (TGA) method. Coals were provided from two different coal mines in the Aegean region of Turkey. Oxy-fuel combustion experiments were carried out with three different gas mixtures of 21% O2–79% CO2; 40% O2–60% CO2 and 50% O2–50% CO2 at 950 °C and heating rates of 10 °C/min, 20 °C/min and 40 °C/min. The kinetics of the oxy-fuel combustion of coals were studied by using four different methods namely, Coats-Redfern (model-fitting method), Friedman (FR), Flynn–Wall–Ozawa's (FWO) and Kissinger–Akahira–Sunose's (KAS) methods. The apparent activation energies of combustion process calculated by FWO method are slightly but systematically higher than that calculated by the KAS and FR methods for the oxy-fuel atmospheres. Combustion behavior of both coals in the oxy-fuel combustion environment could vary significantly, likely due to their characteristics such ash and volatile matter contents.  相似文献   
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