different patterns of pressure systems together with local factors, leads in generation, risingand spread of dust in west of iran. in this study, to investigate the factors causing the occurrence of dust inkermanshah province, 132 cases of dust phenomena (code: 06) were selected and analyzed using kermanshahsynoptic station data for the spring and summer seasons in a period of 5 years (2005-200...

the occurrence of dust storms and their sources in the southern and central parts of iran during the period of 2002 to 2009 was investigated. for this purpose, the meteorological and synoptic data, data from the middle and upper atmosphere, and wind flow tracking model were used. dust storms and nddi were traced using satellite imagery from fasa, shiraz, and bushehr stations. analysis of the gr...

Here, we investigate the possible optical anisotropy of vacuum due to gravitational field. In doing this, we provide sufficient evidence from direct coordinate integration of the null-geodesic equations obtained from the Lagrangian method, as well as ray-tracing equations obtained from the Plebanski’s equivalent medium theory. All calculations are done for the Schwarzschild geometry, which resu...

Knowledge tracing refers to a family of methods that estimate each student’s knowledge component/skill mastery level from their past responses questions. One key limitation most existing is they can only an overall student per since analyze the (usually binary-valued) correctness responses. Therefore, it hard use them diagnose specific errors. In this paper, we extend beyond prediction task pre...