حسن رستگار

A new single-phase transformerless grid-connected PV inverter is presented in this paper. Investigations in transformerless grid-connected PV inverters indicate the existence of the leakage current is directly related to the variable common-mode voltage (CMV), which is presented in detail. On the other hand, in recent years it has become mandatory for the transformerless grid-connected PV inverters to satisfy new grid-codes such as low-voltage ride-through (LVRT) capability via injecting reactive power during grid faults. Therefore, in this paper, the design of the proposed topology is based on retaining the constant CMV to suppress the leakage current and also to provide reactive power injection capability during grid faults. The control strategies for injecting reactive power in the LVRT condition are also examined. To validate the presented theoretical concepts, the performance and dynamic response of the proposed transformerless PV inverter are investigated by MATLAB/Simulink and the simulation results are presented and discussed.

Insects as the largest category of arthropods include numerous groups and families that the most important of them belong to order Diptera, family Culicidae. Because of feeding on the human's blood, a number of species of this family have been known as responsible for the transmission of pathogens for many diseases such as malaria, filariasis, encephalitis, yellow fever and dengue fever in the world. Given that no research has been conducted to determine the fauna of existing mosquitoes in the city of Poldokhtar, Lorestan Province, the present study aimed to exactly determine the mosquitoe's fauna in this city to perform appropriate prevention measures.
In this faunistic and cross-sectional descriptive study, four urban areas and four rural areas in four geographic directions in the city of Poldokhtar were determined. In each urban area, two places and in each designated rural area, four places including two human places and two animal places were selected. From the early of April 2015 to the early of January 2016, larvae, pupae and adult mosquitoes of the Culicidae family were collected. Sampling methods for larvae, pupae and mature were ladling, night catch, total and hand catch with an aspirator. Characteristics including the name of the collector, date of collection, code related to habitat, habitat status (permanent or temporary), type of vegetation cover, type of substrate, and the situation of sunlight were recorded in the related form. The samples were identified by resources and valid identification keys. The data were analyzed using the SPSS software version 19.
Totally, 5392 mosquito adults of the Culicidae family including 1818 mosquito adults and 3574 larvae in designated areas in the city as well as four rural areas were collected. The three genera Anopheles (21.9%), Culex (64.6%), and Culiseta (13.5%) were diagnosed. Also, from three genera, 12 species were identified as follows: Culex theiler, Cx. mimeticus, Cx. perexiguus, Cx. hortensis, Cx. pipiens, Cx. sitiens, Cx. tritaeniorhynchus, Culiseta langiareolata, Anopheles superpictus An. stephensi, An. turkhudi and An. dthali.Culex pipiens (19.9.5%) and Culex theileri (19.5%) were the most abundant species, respectively.
The results of this study indicate the presence of various species of mosquitoes throughout the city of Poldokhtar. Also, the results can lay the groundwork for doing more comprehensive and special studies particularly regarding the possible role of different species of mosquitoes in human and animal health in the future.

This paper is concerned with the generation control in small stand-alone MicroGrids consisting of inverter interfaced Distributed Generation (DG) units. An intelligent and on line Microgrid Management System (MGMS) using Artificial Neural Network (ANN) controller is used in this study and it determines the amount of power produced from generation units in a stand-alone MicroGrid. The ANN trained with a data generated from a Genetic Algorithm (GA) solved optimal power flow problem, which defines generation unit’s power in order to have a minimum power loss in the system, considering normal buses voltage and rating of generation units. Simulation results in a typical distribution system consisting two DG units show that the proposed method can meet the requirements of the system and DG units rating in stand alone operations. In this way the system is managed in an on-line, optimal, and reliable situation that guarantee the continuity of power to loads in stand-alone mode of a MicroGrid.

Textbooks, one of the most popular forms of instructional media, are used to teachstudents at the most levels and in the most subject areas. The purpose of thisresearch is to evaluate the role of graphic in designing and preparing universitytextbooks in order to present an applied model. This study also involvesconsideration of the effect of the demographical variables (gender, age, academicfield, academic terms and Average) in student's viewpoint to examine graphicaldesign of university textbooks. A descriptive method and a visual content analysiswere performed in this research. Therefore, in this study two statistical procedureswere conducted. The first procedure includes an evaluation of graphical designs ofthe university textbooks by 267 students from psychology and educational sciencefaculty of Tarbiat Moalem University. The second procedure includes the visualcontent analysis of 40 books on behavioral and educational Science areas publishedby international publishers such as: John Wiley & Sons, McGraw-Hill, Rutledge andSAGE. The information gathering tools were a graphical design questionnaires and achecklist. The questionnaire was implemented and all the data were analyzed andalpha coefficient was computed. The reliability coefficients obtained were: 0.60 forCover Design Factor, 0.82 for Text Design Factor, 0.83 for Picture And TableDesign Factor, 0.88 for Photography and Portrait Design Factor and 0/74 for PageDesign Factor. The analysis of data was performed at two levels: the first levelinvolved the descriptive statistics such as frequency, percentage, mean and standarddeviation. The second level involved the inferential statistics including One SampleT Test, Friedman test and Chi-Square test. The result of the first study showed thatstudent's viewpoint of graphical designs of textbooks was significantly below theaverage level considered for the study (p≤0.01). Moreover demographic variablessuch as gender, age, academic field, academic terms and Average of the studentswere significantly influential on their evaluation of graphical designs of universitytextbooks (p≤0.05). The visual design examination of the foreign textbooks showedthat in graphical designing of the textbooks a plethora of principles and factorsshould be considered.