following the 1994 northridge and 1995 kobe earthquakes, most of modern structures damaged seriously or devastated totally despite the seismic codes of these countries that had been expected to bear advanced criteria for seismic design of structures. after extensive research, the most probable reason of those destructions was attributed to special specifications of near-field earthquakes. in th...

The main focus of this research has been to investigate the effectiveness of optimal single and multiple Tuned Mass Dampers (TMDs) under different ground motions as well as to develop a procedure for designing TMD and MTMDs to be effective under multiple records. To determine the parameters of TMD and MTMDs under multiple records various scenarios have been suggested and their efficiency has be...

Typically, to study the effects of consecutive earthquakes, it is necessary to consider definite intensity levels of the first shock. Methods commonly used to define intensity involve scaling the first shock to a specified maximum interstorey drift. In this study the structure’s predefined elastic spectral acceleration caused by the first shock is also considered for scaling. This study aims to...

The study of the Earth’s electromagnetic fields prior to the occurrence of strong seismic events has repeatedly revealed cases were transient anomalies, often deemed as possible earthquake precursors, were observed on electromagnetic field recordings of surface, atmosphere and near space carried out measurements. In an attempt to understand the nature of such signals several models have been pr...

the algal flora of five stations from paddy-fields of golestan province was investigated between october 2006 and september 2007. eight filamentous heterocystous nostocacean are recorded here for the first time from paddy fields of iran: cylindrospermum licheniforme, cylindrospermum stangnale, cylindrospermopsis raciborskii, calothrix ghosei, gloeotrichia longiarticulata, aulosira implexa var. ...

In order to conduct empirical casualty modelling in China, Chinese historical earthquake events is the essential basis. However, commonly used casualty databases that focus on Chinese earthquakes and provide comprehensive information rarely exist. Regarding this situation, we derived an earthquake casualty database of Mainland China from authorized Chinese published data sources. The casualty d...

BACKGROUND Earthquakes and other catastrophic events frequently occurring worldwide can be considered as outliers and cause a growing and urgent need to improve our understanding of the negative effects imposed by such disasters. Earthquakes can intensively impact the birth outcomes upon psychological and morphological development of the unborn children, albeit detailed characteristics remain o...