Natural hazards such as earthquakes have threatened the life of human beings during the history.As a consequence, the vibration mitigation of structures has caught great importance. Activecontrol of structures is one of the rapidly emerging areas in the concept of structural control. Thispaper presents a control method to deal with this subject when the dynamics of the structure ishysteretic an...

Introduction: Nowadays, Imaging of the myocardial perfusion (MPI) using the single photon emission tomography (SPET) in the diagnosis of coronary artery disease, especially myocardial ischemia, is of great importance. In contrast to the coronary artery angiography, MPI is non-invasive, less expensive and more physiological. Unfortunately, this image is affected by the some artifacts. Thes...

In this work an N-state Markov Chain model is attempted to validate, which is used to generate an attenuation time series. The model is applicable for estimating the CCDFs (complement cumulative distribution function) of attenuation. The state transition probability parameters of the model is determined from fade slope statistics of attenuation. The conditional probability density function of f...

development of ultrasound technique has not been progressing for evaluating the internal quality of fruits as fast as that of processed foods. in this research for quality assessment of pear fruit (shah miveh variety) an ultrasonic measurement system was constructed to transmit and receive the ultrasonic waves. the apparatus included a pulser-receiver, a pair of 75 khz ultrasonic transducers wi...

quantitative ultrasound (qus) is a noninvasive, inexpensive and portable method for bone densitometry. it may measure some other parameters in addition to bmd, like elasticity and micro architecture. this study designed to determine the relation between reproductive factors and calcaneus qus parameters in normal women of tehran. bmd of heel in 151 normal women, 20-72y/o (participator of iranian...

Purpose: Fiber carbon is the most common material used in treating couch as it causes less beam attenuation than other materials. Beam attenuation replaces build-up region, reduces skin-sparing effect and causes target volume under dosage. In this study, we aimed to evaluate beam attenuation and variation of build-up region in 550 TxT radiotherapy couch.Materials and Methods: In this study, we ...

background: attenuation coefficient (μ) plays an important role in calculations of treatment planning systems, as well as determination of dose distributions in external beam therapy, dosimetry, protection, phantom materials and industry. so, its exact measurement or calculation is very important. the aim of this study was to evaluate the μ in different points in the water phantom analytically ...

The linear attenuation coefficient (LAC) and mass (MAC) are most important while studying of radiation, radio-isotopes in dosimentry irradiation materials. In the present work to calculate values different salts samples by using Gamma-ray spectrometry with Photo-Multiplier Tube (PMT) Multi-Channel Analyzer (MCA). 0.123, 0.511, 0.662, 1.17, 1.28 1.33MeV gamma energy rays used for experiment inte...

The EMI filters are usually used for suppression of electromagnetic conducted interference of range 9 kHz-30 MHz. The efficiency of electromagnetic interference filter is described by attenuation characteristics. The value of attenuation of EMI filter depends on main parameters of filter’s elements and its parasitic parameters. Therefore the high frequency model of electromagnetic interference ...