in many seismological applications, the earth is considered as a perfectly elastic, homogeneous, and isotropic body. although this assumption is approximately valid, it is known that seismic waves pass through the real earth that is anelastic, inhomogeneous and anisotropic.  we consider four processes that can reduce wave amplitude, i.e.: geometrical spreading, scattering, multi-pathing, and an...

road accident severity may be influenced by a number of various systematic causal factors. the weather and road accidents have a close relationship with each other and a number of methods have been proposed for measuring the risk of a road accident with rainy, foggy, and snowy weather and high winds. recent studies indicate that road collision rates increase during precipitation. the weather wa...

The thesis deals with the theory of Generalized Dynamic Factor Models. These models have been introduced about 10 years ago by two groups simultaneously and have been discussed intensively since then. The reason why this model class attracts so many different research groups is, that it is, up to now, the most general class of factor models. The new aspect of these models is, that the spectrum ...

Objective(s):To study the effect of low-frequency vibration on bone marrow stromal cell differentiation and potential bone repair in vivo. Materials and Methods:Forty New Zealand rabbits were randomly divided into five groups with eight rabbits in each group. For each group, bone defects were generated in the left humerus of four rabbits, and in the right humerus of the other four rabbits. To t...

background : we conducted the present study to investigate the frequency of prothrombin g20210a mutation among acute lymphoblastic leukemia patients and healthy individuals from western iran and to detect the possible association between this mutation and the risk of acute lymphoblastic leukemia in our population. methods : the studied groups consisted of 92 children with acute lymphoblastic le...

introduction radiofrequency planar microcoils are used to increase the resolution of magnetic resonance images of small samples. in this study, we aimed to design and fabricate a spiral planar microcoil constructed on a double-sided printed circuit board (pcb). it has four rings with an internal diameter of 241 microns tuned and matched at 63.8 mhz. materials and methods to achieve the maximum ...

Authentication has an important role in many RFID applications for providing security and privacy. In this paper we focus on investigating how RFID can be used in product authentication in supply chain applications and a review of existing approaches is provided. The different categories of RFID product authentication approaches are analyzed within the context of anticounterfeiting and fields w...

General packet radio service (GPRS) is designed for transmitting packet data and supposed to take its radio resource from the pool of channels unused by GSM voice services. Obviously, the introduction of GPRS affects on the voice services. In this paper the outage probability of non-frequency hopping and frequency hopping systems with different frequency reuse factor has been calculated in ord...