insurers have in the past few decades faced longevity risks - the risk that annuitants survive more than expected - and therefore need a new approach to manage this new risk. in this dissertation we survey methods that hedge longevity risks. these methods use securitization to manage risk, so using modern financial and insurance pricing models, especially wang transform and actuarial concepts, ...

rivers and runoff have always been of interest to human beings. in order to make use of the proper water resources, human societies, industrial and agricultural centers, etc. have usually been established near rivers. as the time goes on, these societies developed, and therefore water resources were extracted more and more. consequently, conditions of water quality of the rivers experienced rap...

data envelopment analysis (dea) is a powerful tool for measuring relative efficiency of organizational units referred to as decision making units (dmus). in most cases dmus have network structures with internal linking activities. traditional dea models, however, consider dmus as black boxes with no regard to their linking activities and therefore do not provide decision makers with the reasons...

today, scouring is one of the important topics in the river and coastal engineering so that the most destruction in the bridges is occurred due to this phenomenon. whereas the bridges are assumed as the most important connecting structures in the communications roads in the country and their importance is doubled while floodwater, thus exact design and maintenance thereof is very crucial. f...

abstract nowadays, the science of decision making has been paid to more attention due to the complexity of the problems of suppliers selection. as known, one of the efficient tools in economic and human resources development is the extension of communication networks in developing countries. so, the proper selection of suppliers of tc equipments is of concern very much. in this study, a ...

nowadays in trade and economic issues, prediction is proposed as the most important branch of science. existence of effective variables, caused various sectors of the economic and business executives to prefer having mechanisms which can be used in their decisions. in recent years, several advances have led to various challenges in the science of forecasting. economical managers in various fi...

the present study aimed to investigate representation of discourse markers and metadiscourse markers in conversations and readings of general elt coursebook series used in the language centers of iran. to this aim, four elt coursebooks popularly taught in language centers of this country were analyzed based on fung and carter’s (2007) framework regarding discourse markers and hyland’s (2005) fr...

there are two major theories of measurement in psychometrics: classical test theory (ctt) and item-response theory (irt). despite its widespread and long use, ctt has a number of shortcomings, which make it problematic to be used for practical and theoretical purposes. irt tries to solve these shortcomings, and provide better and more dependable answers. one of the applications of irt is the as...

abstract this paper discusses several commonly used models for strategic marketing¹ including market environmental analysis methods (i.e. swot and pest analysis) and strategic marketing tools and techniques (i.e. boston matrix and shell directional policy matrix)and shows how these models may help a firm to achieve its strategic goals. at first, the main reason for doing this research is de...

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...