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Aim: Positive mood and cognitive flexibility are known to enhance creativity. The present study examines this important issue in the age range of 8 to 12 years, assuming that positive mood is likely to promote creativity by affecting cognitive flexibility. Methods: The study population included all female students aged 8 to 12 years in districts 4 and 8 of Tehran. From the research population, 60 people in two age groups of 8 to 10 (8/80 ± 0/76) and 10 to 12 (11/20 ± 0/76) years were selected by available sampling method. After randomly placing individuals in research groups based on the induced mood and age, individuals were assessed using the computerized version of Wisconsin Card Sorting (1948) and the Torrance Creative Thinking (1974) test. The collected data were analyzed using independent t-test, Pearson correlation coefficient, Mann-Whitney U and Hayes mediator regression model (2018). Results: Regression model analysis confirmed the mediating role of cognitive flexibility between mood and creativity, where positive mood improves individuals' cognitive flexibility and thereby enhances performance in creativity test. Conclusion: The findings of this study as evidence of the importance of mood on the level of cognitive flexibility and creative performance in children emphasized the need to consider this issue in educational settings with the aim of creating and strengthening creative thinking in children. [ABSTRACT FROM AUTHOR]

This experimental study investigated the performance of Catechol degradation by US/TiO2/H2O2 process as an integrated advance oxidation process. In this experimental study, initial pH, dose of TiO2, initial concentration of Catechol, H2O2 concentration and reaction time parameters optimised BBD. The results suggest that US/TiO2/H2O2 process has a high efficiency in Catechol degradation. Optimum condition of US/TiO2/H2O2 process is pH = 3.43, H2O2 concentration = 130 mg/l, TiO2 dose = 0.34 g/l, Catechol concentration = 12.52 mg/l and reaction time = 70.64 min. According to predicate point, the percentage of Catechol removal in this condition was 96.2 and 92.34 as a predicated and experimental percentage of Catechol removal by this process. The kinetics of reaction follows pseudo-first-order kinetic. The synergist effect of sonolysis, TiO2 and H2O2 is 2.09 fold. 70 and 63% of initial COD and TOC were removed. Presence of radical scavenger has an adverse impact on the performance of US/TiO2/H2O2 process. [ABSTRACT FROM AUTHOR]

This paper proposes a non-linear optimization Interior Point (IP) method for the determination of maximum loadability in a power system. Details of the implementation of pure primal-dual and predictor-corrector primal-dual IP algorithms are presented. It is shown that most of the computational effort of the algorithm is taken by the formation and factorization of the augmented Hessian matrix of the IP algorithm. The size of this matrix can be as large as ten times the number of buses in the system. Comparisons of the two IP implementations with large scale power systems with as many as 4000 buses are presented. It is shown that the IP algorithm constitutes an effective method for the determination of the maximum loadability in a power system. Keywords: Power system optimization, maximum loadability, interior point algorithms, voltage stability.

The comparison of performance of four methods for contingency screening and ranking for voltage stability analysis is presented. Three of the methods are existing methods, while a new method is proposed. The performance of all the methods is carried out by comparing with full solutions using a continuation power flow. It is shown that the newly proposed method has the best performance in terms of accuracy and computation time. All the methods are evaluated using a 234-bus system. Additional results using the best performing method are included for a 901-bus power system. Keywords: Voltage stability, continuation power flow, contingency screening and ranking, saddle node bifurcation, voltage collapse.

This paper discusses the Issues which must be addressed when integrating Artificial Intelligence (AI) and, in particular, expert system applications in an Energy Management System (EMS) environment. It is argued that these issues can be resolved by creating an environment which supports all the interfaces between the Artificial Intelligence (AI) applications and the EMS. This environment should also be responsible for maintaining a model of the power system common to all the AI applications. Once this environment has been created, AI applications can be easily 'plugged' into the EMS. The design of such an environment is described and case studies of its implementation are provided to illustrate its flexibility. Keywords: Power systems, artificial intelligence, energy management systems, topology processing.

This paper presents an efficient approach to short term resource scheduling based on the augmented Lagrangian relaxation method. The problem is divided into two stages, the commitment stage and the constrained economic dispatch stage. The proposed mathematical model incorporates optimal power, flow (OPF) constraints in the unit commitment stage. By OPF constrains, we refer to the relevant active power constraints that are incorporated in the constrained economic dispatch stage (i.e. transmission capacity constraints, fuel and various regulated emission requirements). The inclusion of OPF constraints in the commitment stage will improve the feasibility of the constrained economic dispatch solution. Other unit commitment constraints such as spinning and operating reserve requirements, power balance as well as other relevant local constraints (i.e. unit ramping rates, upper and lower generation limits, minimum up and down times) are taken into account in the proposed model. As we deal with a larger number of constraints, a more rigorous method is introduced for updating Lagrange multipliers to improve the solution convergence. A software package which addresses energy management systems requirements is developed and tested. Keywords: Resource Scheduling, Augmented Lagrangian Relaxation, Fuel Constraints, OPF Constraints

In this experimental study, alum adsorbent was synthesized using an electrochemical process consisting of aluminum (anode) and iron (cathode) electrodes in a 1 L cylindrical reactor. The structure of the alum adsorbent was investigated using transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and Brunauer--Emmett--Teller techniques. Adsorption process experiments were evaluated with four input parameters such as pH (4-9), alum nanoparticles dosage (0.01-0.05 g/L), initial concentration of tannic acid (10--80 mg/L), and contact time (5-50 min). The isotherm and adsorption kinetics were examined under optimal experimental conditions to evaluate the adsorption process. The results of the physicochemical analysis confirmed the accuracy of the alum structure. Under optimal conditions of the adsorption process, pH, adsorbent dose, initial concentration of tannic acid, and contact time were 6, 0.05 g/L, 20 mg/L, and 50 min; Under these conditions, the removal efficiency of tannic acid was obtained to be 93.9%. The results of the adsorption isotherm and kinetics studies showed that the adsorption process follows the Langmuir isotherm (R² = 0.99) while the process kinetics corresponds to the second-order kinetics model (R² = 1). The results showed that alum can be used as a high-availability and cost-effective adsorbent to remove tannic acid from aqueous solutions. [ABSTRACT FROM AUTHOR]

In this experimental study, the statistical response surface methodology (RSM) based Box-Behnken design (BBD) was selected for evaluation of the effect of different parameters (solution pH,H2O2 concentration, current density, and time) and their interactions on the degradation of the diazinon by electro Fenton process. The results showed that the quadratic model is suitable for the obtained data (P-value = 0.0001) and in optimal process performance conditions was set equal to 100%. Regression analysis with a high correlation coefficient (R2 = 0.9980) and the model value of 765.56 indicated the adequacy of the model. Based on the results, the electro-Fenton process is an efficient technique for removing diazinon from aqueous media. [ABSTRACT FROM AUTHOR]

The coloured wastewater from the textile industries may show toxic or carcinogenic effects on the organism, when discharged into the rivers and lakes, which are changing their biological life. Therefore, in this study, the removal of basic violet 16 was investigated by a magnetite graphene oxide nanocomposites (Fe3O4@GO) optimising by the response surface methodology based on Box–Behnken method. Fe3O4@GO nanocomposite was prepared by a facile in situ co-precipitation method, resulting in a suitable composite for the adsorption of dye. The structure and morphology of the Fe3O4@GO adsorbent were investigated using XRD, FT-IR, SEM, BET and VSM techniques. Base on the SEM images, the Fe3O4 NPs were distributed between the GO sheets and empty spaces with visible large pores between GO sheets. Also, the results of the FT-IR analysis showed that the dominant group was carboxyl group. The various parameters were evaluated in the process such as pH, reaction time, adsorbent dose and initial concentration of dye. The proposed model (quadratic) was approved with a high correlation coefficient (R2 = 0.98) and (R2adj = 0.97). Desirable removal of dye (efficiency: 95.03%.) was obtained under following conditions: the dye concentration of 62.5 mg L−1, the absorbance of 0.2 g L−1, the reaction time of 60 min and solution pH of 7.5. The results of isotherms and kinetics adsorption study showed that the adsorption process follows the Langmuir isotherm (R2: 0.98) and the pseudo-second-order kinetic (R2: 0.99) models. The present study showed that the Fe3O4 @GO adsorbent has a high efficiency in the removal of violet 16. [ABSTRACT FROM AUTHOR]

The renal capsule tissue of lamb was irradiated with ultraviolet-C light and the treated samples were analyzed by uniaxial tensile test, dynamic mechanical analysis, attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and contact angle measurements. It was shown that the skin cross-linking is dominant in low doses in accordance with the contact angle assessment. Conversely, the strong bulk degradation takes place at high doses. Similarly, the bulk cross-linking affects the mechanical tests as to enhance the stiffness at low doses, whereas strong degradation occurs at high doses that mainly arises from the strong bulk chain scission. [ABSTRACT FROM AUTHOR]

This study has been carried out with the aim of evaluating the treatability of polycyclic aromatic hydrocarbon compounds of PAHs available in urban and industrial sewage sludge utilizing advanced chemical oxidation methods contingent on free sulfate radicals using hydrogen peroxide and heat activation methods. For this purpose, various parameters including (3, 5, 7, 9, and 10), persulfate's concentration (2, 10, 5, 15, and 20 mmol), the ratio of peroxide to persulfate (1, 0.5, 0.3, 0.2, and 0.1), sludge temperature (25°C, 35°C, 45°C, and 55°C) and the primary concentration of PAHs were considered at the 20 d reaction periods. Through making use of gas chromatography- mass spectrometry (GC-MS), after 40-min period, the quality and quantity of the compounds available in the samples were determined using a mass detector and the drawn standards curve. After examining the effectiveness of eliminating PAH compounds in various conditions, the chemical oxygen demand test was carried out for the samples related to optimal removal of PAH compounds to determine the real efficiency of the process in eliminating intermediate compounds originated from PAHs oxidation. The results demonstrate that the advanced chemical oxidation method (persulfate-peroxide) can effectively result in the elimination of PAH compounds from the sludge. [ABSTRACT FROM AUTHOR]