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This study was conducted to monitor and evaluate the health risks of multiple organophosphorus pesticide residues in three characteristic fruits of Maragheh district, East Azerbaijan province. The Monte Carlo method was used to quantify the possible non-carcinogenic health risks associated with pesticide residues in adults and children. The residues of 17 pesticides in 36 samples were analysed using the QuEChERS extraction method coupled with gas chromatography-mass spectrometry (GC/MS). Residues of 13 pesticides (76.47%) were detected in grape samples and 15 pesticides (88.23%) in apricot and plum samples. The maximum level found in grape samples was due to chlorpyrifos with 1.2 mg/kg, and in apricot and plum samples to diazinon with 1.6 and 1.3 mg/kg, respectively. All grape, apricot and plum samples contained at least ten pesticides with levels exceeding the Iranian and EU Maximum Residue Limits (MRLs). The processing factor for washing treatment in grape, apricot and plum samples was less than 1, ranging from 0.53 to 0.69. Chlorpyrifos with values of 0.064 and 0.256 in the grape samples and diazinon with values of 0.0443 and 0.177 in the apricot samples and values of 0.0263 and 0.105 in the plum samples contain the highest hazard quotients (HQ) for adults and children, respectively. The cumulative risk assessment due to exposure to several pesticide residues suggests that there is no significant health risk for adults (HI < 1). However, consumption of unwashed grapes may cause adverse effects in children (HI = 1.48). However, for further research, a comprehensive longitudinal study is suggested to assess the long-term effects of exposure to pesticides especially for children. [ABSTRACT FROM AUTHOR]

The objective of this article is to propose a model for the professional competencies of managers based on the Fundamental Reform Document of Education (FRDE). The research employed an applied mixed method study (qualitative-quantitative) with an exploratory approach. Qualitative stage participants consisted of faculty members of the Islamic Azad University of Tehran, staff specialists of the Ministry of Education, and senior organization managers. The quantitative stage target population comprised all middle school educational managers in Tehran city, from which 335 individuals were selected using the cluster sampling method and Morgan's table. A researcher-designed questionnaire was used to collect data, and structural equation modeling was utilized to analyze the data. The results revealed that six areas were identified concerning the professional competence of the managers of the country's education system. These six areas include personal competence, moral competence, technical competence, administrative competence, organizational competence, and communication competence, each of which had sub-components suitable for the country's school management system's needs and requirements. [ABSTRACT FROM AUTHOR]

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The smart grid is an electric grid that can deliver electricity in a controlled and two-way smart connection from points of generation to active consumers. A communication infrastructure is an essential part to the success of the emerging smart grid. A scalable and pervasive communication infrastructure is crucial in both construction and operation of a smart grid. To deal with the communication problem of smart grids, specifically increasing the speed of data flow, mobile data offloading technique can be used. Performance of mobile data offloading depends on the sites of deployed access points. In this paper, a novel genetic algorithm with ability to deal with premature convergence to increase the performance of data offloading is presented. [ABSTRACT FROM AUTHOR]

In this paper, the stator/rotor currents control problem of doubly-fed induction generator under faulty line voltage is carried out. Common grid faults cause a steep decline in the line voltage profile, commonly denoted as voltage dip. This point is critical for such kind of machines, having their stator windings directly connected to the grid. In this respect, solid methodological nonlinear control theory arguments are exploited and applied to design a novel controller, whose main goal is to improve the system behaviour during voltage dips, endowing it with low voltage ride through capability, a fundamental feature required by modern Grid Codes. The proposed solution exploits both feedforward and feedback actions. The feedforward part relies on suitable reference trajectories for the system internal dynamics, which are designed to prevent large oscillations in the rotor currents and command voltages, excited by line perturbations. The feedback part uses state measurements and is designed according to Linear Matrix Inequalities (LMI) based saturated control techniques to further reduce oscillations, while explicitly accounting for the system constraints. Numerical simulations verify the benefits of the internal dynamics trajectory planning, and the saturated state feedback action, in crucially improving the Doubly-Fed Induction Machine response under severe grid faults. [ABSTRACT FROM AUTHOR]