mohammad hossein bahrami - Academia.edu (original) (raw)

Papers by mohammad hossein bahrami

Research paper thumbnail of Analysis of the Dynamic Soil-Pile Interaction During the Passage of Rayleigh Waves Using Fourier Transform

The modeling and calculation of dynamic response of single-pile under Rayleigh waves is investiga... more The modeling and calculation of dynamic response of single-pile under Rayleigh waves is investigated in this paper. For the shallow buried underground structures, Rayleigh waves can be the key factor to control the responses and damage of the structure. Closed-form expression for the horizontal displacement distributions is evaluated using Fourier transform and presented when the pile tip is free-head and fixed-head, with realistic frequency-dependent 'springs' and 'dashpots'. The analytical results are for both piles with finite or infinite length. The dynamic response of piles to seismic loading is explored by means of an extensive parametric study based on a properly calibrated Beam-on-Dynamic-Winkler-Foundation (BDWF) model. This study has shown that a simple analytical solution was found to be in excellent agreement with the results of a rigorous solution; a parametric study for various soil type and pile properties is done and for the horizontal displacement component is obtained for the infinitely long-pile formulation and piles with finite length; It is mentioned that for very stiff piles or very soft soils at high frequencies, some noticeable differences between the two types of piles will be begun.

Research paper thumbnail of Microfacies and sedimentary environments of Dalan Formation at Surmeh Mountain, Folded Zagros Zone, southwestern Iran

International Journal of Basic and Applied Sciences, 2012

The Permian carbonates-evaporates Dalan Formation is one of the most important gas reservoir in t... more The Permian carbonates-evaporates Dalan Formation is one of the most important gas reservoir in the Zagros Basin. The Zagros are located on the boundary between the Arabian and Eurasian lithosphere plates and are the Orogenic response to a collision between Eurasia and advancing Arabia during the Cenozoic. The study area is located at the eastern part of Surmeh Mountain, ~120 km south of Shiraz in the Folded Zagros Zone. Dalan Formation at Surmeh Mountain, with a thickness of 650 meters, is formed of three lithostratigraphic units. These units, from bottom to top, consist of Lower Dalan, Nar Member and Upper Dalan. The careful examination of thin sections led to the recognition of six microfacies which was performed on the basis of skeletal and non-skeletal grains and matrix (fenesteal dolomitic mudstone, layered anhydrite, lagoonal skeletal wackstone/ packstone, fine-grained ooid, peloid grainstone with lagoonal skeletal debris, medium-grained ooid grainstone with oomoldic porosity, open marine fossiliferous mudstone). Microscopic and macroscopic evidences show that Dalan Formation facies can be divided into four facies belts, on the basis of depositional features, specific of carbonate platforms of homoclinal ramp type. These belts include tidal flats, lagoons, shoal and basin environments. Mohammad Bahrami et. al.

Research paper thumbnail of Survey of Medical Residents’ Attitude Toward Physical Medicine and Rehabilitation

American Journal of Physical Medicine & Rehabilitation, 2014

This survey was completed on 600 medical residents in 19 randomly selected teaching hospitals fro... more This survey was completed on 600 medical residents in 19 randomly selected teaching hospitals from three Iranian medical universities to delineate some possible factors associated with medical residents' awareness of and attitude toward 11 specified areas of physical medicine and rehabilitation (PM&R). Fifty-four percent of the participants had a history of consultation with physiatrists. Male residents and those with history of general medicine education in a university having a residency program in PM&R were the most likely to consult with physiatrists. Age and graduation date were not significant predictors of consultation. Residency specialty was the most powerful covariate of consultation rate, with the highest rate of consultation in neurosurgery, neurology, and orthopedics. The best known areas of PM&R were rehabilitation of central nervous system disorders, electrodiagnostic studies, and prescription of physical modalities. The most requested areas of PM&R for collaboration were therapeutic exercise, musculoskeletal and rheumatic disorders, and geriatric rehabilitation. Overall, the residents of various specialties showed different levels of familiarity and attitude toward the different areas of PM&R. This indicates that specific programs are needed to improve PM&R collaboration with all specialties. Policy makers in all levels, from hospital administrators to the ministry of health, need to further enhance the familiarity of medical residents with the field PM&R.

Research paper thumbnail of Analysis of the Dynamic Soil-Pile Interaction During the Passage of Rayleigh Waves Using Fourier Transform

The modeling and calculation of dynamic response of single-pile under Rayleigh waves is investiga... more The modeling and calculation of dynamic response of single-pile under Rayleigh waves is investigated in this paper. For the shallow buried underground structures, Rayleigh waves can be the key factor to control the responses and damage of the structure. Closed-form expression for the horizontal displacement distributions is evaluated using Fourier transform and presented when the pile tip is free-head and fixed-head, with realistic frequency-dependent 'springs' and 'dashpots'. The analytical results are for both piles with finite or infinite length. The dynamic response of piles to seismic loading is explored by means of an extensive parametric study based on a properly calibrated Beam-on-Dynamic-Winkler-Foundation (BDWF) model. This study has shown that a simple analytical solution was found to be in excellent agreement with the results of a rigorous solution; a parametric study for various soil type and pile properties is done and for the horizontal displacement component is obtained for the infinitely long-pile formulation and piles with finite length; It is mentioned that for very stiff piles or very soft soils at high frequencies, some noticeable differences between the two types of piles will be begun.

Research paper thumbnail of Microfacies and sedimentary environments of Dalan Formation at Surmeh Mountain, Folded Zagros Zone, southwestern Iran

International Journal of Basic and Applied Sciences, 2012

The Permian carbonates-evaporates Dalan Formation is one of the most important gas reservoir in t... more The Permian carbonates-evaporates Dalan Formation is one of the most important gas reservoir in the Zagros Basin. The Zagros are located on the boundary between the Arabian and Eurasian lithosphere plates and are the Orogenic response to a collision between Eurasia and advancing Arabia during the Cenozoic. The study area is located at the eastern part of Surmeh Mountain, ~120 km south of Shiraz in the Folded Zagros Zone. Dalan Formation at Surmeh Mountain, with a thickness of 650 meters, is formed of three lithostratigraphic units. These units, from bottom to top, consist of Lower Dalan, Nar Member and Upper Dalan. The careful examination of thin sections led to the recognition of six microfacies which was performed on the basis of skeletal and non-skeletal grains and matrix (fenesteal dolomitic mudstone, layered anhydrite, lagoonal skeletal wackstone/ packstone, fine-grained ooid, peloid grainstone with lagoonal skeletal debris, medium-grained ooid grainstone with oomoldic porosity, open marine fossiliferous mudstone). Microscopic and macroscopic evidences show that Dalan Formation facies can be divided into four facies belts, on the basis of depositional features, specific of carbonate platforms of homoclinal ramp type. These belts include tidal flats, lagoons, shoal and basin environments. Mohammad Bahrami et. al.

Research paper thumbnail of Survey of Medical Residents’ Attitude Toward Physical Medicine and Rehabilitation

American Journal of Physical Medicine & Rehabilitation, 2014

This survey was completed on 600 medical residents in 19 randomly selected teaching hospitals fro... more This survey was completed on 600 medical residents in 19 randomly selected teaching hospitals from three Iranian medical universities to delineate some possible factors associated with medical residents' awareness of and attitude toward 11 specified areas of physical medicine and rehabilitation (PM&R). Fifty-four percent of the participants had a history of consultation with physiatrists. Male residents and those with history of general medicine education in a university having a residency program in PM&R were the most likely to consult with physiatrists. Age and graduation date were not significant predictors of consultation. Residency specialty was the most powerful covariate of consultation rate, with the highest rate of consultation in neurosurgery, neurology, and orthopedics. The best known areas of PM&R were rehabilitation of central nervous system disorders, electrodiagnostic studies, and prescription of physical modalities. The most requested areas of PM&R for collaboration were therapeutic exercise, musculoskeletal and rheumatic disorders, and geriatric rehabilitation. Overall, the residents of various specialties showed different levels of familiarity and attitude toward the different areas of PM&R. This indicates that specific programs are needed to improve PM&R collaboration with all specialties. Policy makers in all levels, from hospital administrators to the ministry of health, need to further enhance the familiarity of medical residents with the field PM&R.