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...

section{introduction} the concept of {sl cartan geometry} appeared at the beginning of the twentieth century, when {e}lie cartan was working on the so-called {sl equivalence problem}, the aim of which is to determine whether two given geometric structures can be mapped bijectively onto each other by some diffeomorphism. this problem can be considered in many different contexts, such as ...

due to the limiting workspace of parallel manipulator and regarding to finding the trajectory planning of singularity free at workspace is difficult, so finding a best solution that can develop a technique to determine the singularity-free zones in the workspace of parallel manipulators is highly important. in this thesis a simple and new technique are presented to determine the maximal singula...

abstract when in administrative law the matter of administrative offences are raised, these offences would have legal nature if they are force able, some of these offences are related to administrative law, where as some other pelts are common in civil or penal law. the current research intends not only to consider the concept and foundation of administrative execution rules but also compares...

teachers’ beliefs greatly influence their performance in the classroom, their choice of instructional strategies, their way of controlling the class, their dealing with the students, and their general goals and objectives. one of these beliefs is teachers’ sense of efficacy which is viewed as an important construct and has shown to be positively correlated with students’ achievement (ross, 1992...

implicit and unobserved errors and vulnerabilities issues usually arise in cryptographic protocols and especially in authentication protocols. this may enable an attacker to make serious damages to the desired system, such as having the access to or changing secret documents, interfering in bank transactions, having access to users’ accounts, or may be having the control all over the syste...

language learning courseware has been receiving growing attention by english educators since its advent. a variety of softwares have been designed by software designers and resorted to by language educators to supplement language textbooks. this experimental study investigated how the application of computerized version of language textbooks and the reception of the entire course through comput...

‏‎despite the different criticisms on contrastive analysis it has been proved that the results of it(when processed) can be useful in a tefl environment, specially at the level of phonology.this study is an attempt to compare and contrast the sound systems of kurdish and english for pedagogical aims.the consonants,vowels,stress and intonation of the two languages are described by the same model...

abstract:‎ literature is said beautiful words of poetry or prose that excites reader’s or listener’s feel. certainly, to ‎be effective, such a text should have certain characteristics. the four elements of the literature: thought, ‎imagination, emotion and style make a text to be literary and effective. emotion and imagination are ‎specific elements of literary texts, while thought and style a...

this is an original study on the effect of a polyisobutylene – polydimethylsiloxane (pibpdms) block copolymer modifier used as an interfacial active agent on the dynamics behaviour of single newtonian drops suspended in a polyisobutylene (pib) newtonian matrix. the results were divided in two sections. the first part included the experiments carried out on the non-modified and 2% block cop...