when a jack-up installed at a clay location and then leaves; it can create several meter deep footprints. in case of soft clay, the spudcan may have actually penetrated much deeper than the observed footprints. when the penetrated spudcan is pulled out, much of the soft remolded clay will flow around it and go back into the hole. this event, leaving a deep region of disturbed soil. the disturbe...

This paper examines the pull-in behavior of a bio-mass sensor with a cantilevered CNT actuated electrostatically by considering rippling deformation. Although this phenomenon can remarkably change the behavior of CNT, its effect on the performance of a CNT-based mass sensor has not been investigated thus far. This investigation is based on modified Euler-Bernoulli beam theory and rippling effec...

dust storms are natural phenomena which occur in arid and semi-arid areas of the world. in this study, to evaluate the dust storms which occurred in mashhad over a period of 30 years (1981-2009), first, the number of days on which dust storms happened in mashhad (days with a wind speed greater than 15 m.s-1 and horizontal visibility less than 1000 m) were identified and counted for each month; ...

Power system blackouts have become a serious problem for electric utilities especially in recent years. Different forms of system instability have emerged in recent blackouts, such as voltage instability and frequency instability. To counteract each form of system instability, special algorithms have been designed in the protection system, e.g. Under Frequency Load Shedding (UFLS) and Under Vol...

Background and Aim: Degenerative lumbar spine disease can lead to lumbar spine instability. The patients can present with Low Back Pain (LBP), radicular pain, and motor and sensory dysfunction. Age >50, female sex and pregnancies are among prevalent risk factors. The degeneration process usually starts from the intervertebral discs progressing to involve facet joints, ligaments, and vertebral b...

among the agents collection that should observe in instability of rural residences is attention urban dropped sewages ،because of more excecuted works in industvies and home consumption of cities are dealing with water . there fore ،more using of water results in more production of sewage and these sewages have safe place in human consumption cycle. these processes hurt direct evacuation of sew...

landslide like phenomena such as earthquake, flood, and volcano eruption are considered as the important natural events which happen every year in the mountainous and the elevated regions of the country and incur substantial damages and losses. today, in the countries involved with the issue of earthquake sliding, there is an increasing tendency in evaluating and zoning of the danger and damage...

prediction of fluid-elastic instability is a great matter of importance in designing cross-flow tube bundles from the perspective of vibration. in the present paper, the threshold of fluid-elastic instability has been numerically predicted via simulation of incompressible, unsteady, and turbulent cross-flow through a tube bundle in a normal triangular arrangement. the conditions of simulation i...