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61.
Water quality is always one of the most important factors in human health. Artificial intelligence models are respected methods for modeling water quality. The evolutionary algorithm(EA) is a new technique for improving the performance of artificial intelligence models such as the adaptive neuro fuzzy inference system(ANFIS) and artificial neural networks(ANN). Attempts have been made to make the models more suitable and accurate with the replacement of other training methods that do not suffer from some shortcomings, including a tendency to being trapped in local optima or voluminous computations. This study investigated the applicability of ANFIS with particle swarm optimization(PSO)and ant colony optimization for continuous domains(ACO_R) in estimating water quality parameters at three stations along the Zayandehrood River, in Iran. The ANFIS-PSO and ANFIS-ACO_R methods were also compared with the classic ANFIS method, which uses least squares and gradient descent as training algorithms. The estimated water quality parameters in this study were electrical conductivity(EC), total dissolved solids(TDS), the sodium adsorption ratio(SAR), carbonate hardness(CH), and total hardness(TH). Correlation analysis was performed using SPSS software to determine the optimal inputs to the models. The analysis showed that ANFIS-PSO was the better model compared with ANFIS-ACO_R. It is noteworthy that EA models can improve ANFIS' performance at all three stations for different water quality parameters. 相似文献
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Game theory has provided a practical tool to model players' strategic behavior in electricity markets, particularly as the world moves towards a more competitive market. A game theoretic approach can be used to find the clearing electricity price in a retail electricity market with a high penetration of small and mid-size renewable suppliers. 相似文献
64.
Capillary breakup extensional rheometry of associative and hydrolyzed polyacrylamide polymers for oil recovery applications 下载免费PDF全文
High molecular weight polymers used for heavy oil recovery exhibit viscoelasticity that can influence the oil recovery during chemical enhanced oil recovery. Different polymers having similar molecular weight and shear rheology may have different elongation flow behavior depending on their extensional properties. Displacing slugs are more likely to stretch than shear in tortuous porous media. Therefore, it is critical to seek an analytical tool that can characterize extensional parameters to improve polymer selection criteria. This article focuses on the extensional characterization of two polymers (hydrolyzed polyacrylamide and associative polymer) having identical shear behavior using capillary breakup extensional rheometer to explain their different porous media behavior. Maximum extensional viscosity at the critical Deborah number and Deborah number in porous media classified the associative polymer as the one having high elastic‐limit. Extensional characterization results were complemented by significantly higher pressure drop, marginally increased oil recovery of associative polymer in porous media. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46253. 相似文献
65.
Microwave‐assisted polymerization: Inert addition and surface coating of superabsorbent polymer for improved physical properties 下载免费PDF全文
Two different polymerization techniques, microwave‐assisted polymerization and free radical solution polymerization, were utilized in the syntheses of superabsorbent polymers with varying amounts of acrylic acid (31–50%). Degrees of neutralization were in the range of 68–80 mol %, and clay level was varied between 0 and 5%. The base polymer produced with microwave‐assisted polymerization had higher absorbency under low load (0.3 psi) than those with the free radical solution polymerization. To improve its absorbency under higher loads (0.6 and 0.9 psi), the surface coating step was implemented by using ethylene glycol diglycidyl ether as a surface crosslinking agent. Properties such as capacity, permeability, and absorbency under different loads were tested in 0.9% sodium chloride solution for the base and the surface‐coated polymers. In addition, extractables and residual acrylic acid were measured to determine the reaction's efficiency. In conclusion, surface coating improved polymer properties, and the incorporation of clay imparted permeability to the polymer. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43990. 相似文献
66.
Electrical measurements using AC immittance spectroscopic technique over the temperature range of 25-300°C, on sintered compacts of pure BaZrO3 and those containing 5 wt.% BaSnO3 sintered in the temperature range of 1600-1700°C for up to 12 h are reported. Data analyses revealed that the capacitance and the derived dielectric constant remained invariant over more than three decades of frequency in the kilo to megahertz regime. Typically, the average dielectric constant was 15 and the TCK values were P3 and P186 ppm/°C for pure and 5 wt.% BaSnO3-added BaZrO3, respectively, in the range 25-300°C. 相似文献
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A case of primary carcinoma of the urinary bladder associated with a primary retroperitoneal leiomyosarcoma is presented. Due to the lack of early symptoms, diagnosis of the retroperitoneal leiomyosarcoma was late and therefore the prognosis was poor. Twelve months after diagnosis the patient died not of the bladder tumor, but of the recurrent leiomyosarcoma. 相似文献
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Textural Changes in Mushrooms (Agaricus bisporus) Associated with Tissue Ultrastructure and Composition 总被引:2,自引:0,他引:2
The objective of this study was to determine ultrastructural and compositional changes in fresh mushrooms associated with adverse changes in texture during 9 d of post‐harvest storage at 12 °C. Mushroom softening (2.6N to 1.5N, puncturing force) was consistent with toughening (19.2N to 33.0N, gumminess). Protein and total carbohydrate content declined, but chitin content increased during mushroom storage. Most polysaccharides were extracted after deacetylation and depolymerization of chitin, indicating that structural glucans were mainly bound with acetylglucosamine polymers. Softening paralleled expansion of intercellular space at the pilei surface, hyphae shrinkage, central vacuole disruption, and loss of proteins (r = 0.94) and polysaccharides (r = 0.84), while toughening was associated with increased chitin content (r = 0.95). 相似文献