there are many approaches for solving variety combinatorial optimization problems (np-compelete) that devided to exact solutions and approximate solutions. exact methods can only be used for very small size instances due to their expontional search space. for real-world problems, we have to employ approximate methods such as evolutionary algorithms (eas) that find a near-optimal solution in a r...

abstract: in the paper of black and scholes (1973) a closed form solution for the price of a european option is derived . as extension to the black and scholes model with constant volatility, option pricing model with time varying volatility have been suggested within the frame work of generalized autoregressive conditional heteroskedasticity (garch) . these processes can explain a number of em...

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...

for any educational program to be successful, many factors work hand in hand. based on pervious efl studies, teachers and learners are the keys to gain achievement. granted the fact that explicit and implicit practice plays a key role in education, knowledge of it can help teachers facilitate students’ vocabulary learning. this study investigated to determine the contribution of explicit and i...

abstract the present study was conducted to investigate the effectiveness of a rather newly developed method in language teaching that is the use of paragraph reading task and whole reading task and their effects on improving efl learner’s speaking ability. to fulfill the purpose of the study, first 90 participants studying their course at sa eedi high school in tehran were chosen by means of ...

the primary goal of the current project was to examine the effect of three different treatments, namely, models with explicit instruction, models with implicit instruction, and models alone on differences between the three groups of subjects in the use of the elements of argument structures in terms of toulmins (2003) model (i.e., claim, data, counterargument claim, counterargument data, rebutt...

abstract cooperative learning refers to small groups of learners working together as a team to solve a problem, complete a task, or accomplish a common goal. in a cooperative environment one’s success is directly related to the success of other members because the focus on the individual shifts towards the group. to test the effectiveness of the method, using jigsaw technique, a study was cond...

due to extraordinary large amount of information and daily sharp increasing claimant for ui benefits and because of serious constraint of financial barriers, the importance of handling fraud detection in order to discover, control and predict fraudulent claims is inevitable. we use the most appropriate data mining methodology, methods, techniques and tools to extract knowledge or insights from ...

some researches made in the field of agency problem issue, deal with the role of control systems regarding owners and managers. in this research the relationship between the two control mechanisms, namely the voluntary disclosure (external control mechanism) and outside directors (internal control mechanism), which are reductive of agency problems, has been studied. for this reason, a sample ...

the purpose of this study was the relationship between problem – solvi ability with fdi cognitive style of students.the research method was correlation method. for data analysis pearson test was used. statistical society in this research was all the students of alligoodarz city in 1391-92 year.to sampling of statiscal population was used sampling multi-stage random the size of sample selected 2...