in this investigation the effect of external field on the electron density of nanostructures of cds, cdse, cdte, gaas and polymeric structure of three, four, five and six units of cds as a kind of nanosolar cells has been studied theoretically. as modeling this system in nanodimension, molecular structures has used. specific properties of molecular structures permit us to consider different sym...

‎in this article‎, ‎we have focused one some basic and productive information about the properties of spectrum and singular values related to compact operators which are ideals in a c*-algebra of bounded operators‎. ‎considering a two-sided connection between the family of symmetric gauge functions on sequence of singular values of compact operators and symmetric norms on finite dimensional ope...

abstract this study investigates the teachers’ correction of students’ spoken errors of linguistic forms in efl classes, aiming at (a) examining the relationship between the learners’ proficiency level and the provision of corrective feedback types, (b) exploring the extent to which teachers’ use of different corrective feedback types is related to the immediate types of context in which err...

the present study aimed at investigating the relationship between iranian efl teachers’ classroom management orientations and their teaching styles. additionally, the difference between male and female teachers’ teaching styles and classroom management orientations and their relationship with experience and age were explored. three hundred efl teachers filled in attitudes and beliefs on classro...

the purpose of this study was to investigate the effect of task repetition on accuracy of iranian efl learners ’speaking ability. in order to achieve this purpose, a null hypothesis was developed: there is no statistically significant difference between accuracy speaking ability in iranian efl learners by use of task repetition. ; of course i should mention that, beside this null hypothesis, an...

abstract tasks nowadays are at the center of attention in sla research. task types is one of the critical issues in this regard, their effectiveness and suitability to any particular context, their characteristics and the result they yield are among some of these issues. on the other hand, discourse markers (dms) have been very much investigated and their effectiveness in conveying the meaning...

Risks assessment of forest project implementation in spatial density changes of forest under canopy vegetation using artificial neural network modeling approach   Nowadays, environmental risk assessment has been defined as one of the effective in environmental planning and policy making. Considering the position and structure of vegetation on the forest floor, the main role of forest under ca...

Forests areas of Iran in comparison with the world is very low and this low area is in demolition threat always. Hence, the remainder of these forests should be managed based on ecological capability evaluation. With regard to importance of subject, ecological capability for forestry in the Sharui watershed, Khuzestan province, was evaluated in 2015. For this purpose, the Makhdoom model and AHP...

Vegetation in any landscape reflects its health condition. Monitoring land use change and land cover plays a key role in environmental planning and management. Mazandaran province has always been considered by tourists due to its high tourism potential and consequently the vegetation, especially the forest, has been damaged. In this study, vegetation Contiguity and integrity in Mazandaran using...