background: making use of the orthovoltage machines in radiotherapy, is one of the routine methods for the treatment of the superficial lesions. in this study, an important determinant of x-ray quality, the hvl (half value layer), has been evaluated. materials and methods: the hvls of a orthovoltage x-ray machine in 120 and 180 kvp are measured, using an empirical method, in which the hvls are ...

As new technologies become available we need to identify their potential for application. In some cases new technologies are developed in response to specific needs (demand led), in others the technologies are developed and suitable applications are then sought (technology led). In this talk, the potential for applying distributed simulation is discussed. Three modes of simulation practice are ...

introduction: in recent decades, several monte carlo codes have been introduced for research and medical applications. these methods provide both accurate and detailed calculation of particle transport from linear accelerators. the main drawback of monte carlo techniques is the extremely long computing time that is required in order to obtain a dose distribution with good statistical accuracy. ...

abstract use of empirical competition models is one of approaches in integrated weed management strategies. in order to investigation of this approach in simulation of yield loss of bean (phaseolus vulgari. l.) caused by jimson weed (datura stramonium l.) interference, an experiment was conducted in national bean research station, in khomein, in 2007. the experiment design was randomized comple...

a new model based on a combination of the polymeric multigrain and multilayer models has been developed to predict the polymerization rate, particle growth, morphology, effective parameters on broadening of the molecular weight distribution, number and weight average of the molecular weight, isotacticity index and bulk density of polymer. mathematical correlations and the kinetics used in this ...

flood is one of the most calamitous natural disasters that causes extensive property and life damages across theworld. it however, could be a blessing due to its special natural water resources recharging value. by simulating themagnitude of probable floods considering the anthropogenic and natural effects and implementing contingency plans,their damages could be reduced. in this paper, the gen...

pink floyd was a british band whose work began in the late 60s. roger waters, the main contributor of the band, wrote almost all the lyrics and was also a main figure behind producing the motion picture of the album. he deliberately attacks western media in both the lyrics he has written for the band and his solo projects. the present study finds this tendency of assaulting the media deeply roo...

advanced technologies in molecular biology and modern experimental biophysics heavily rely not only on the knowledge of structure of essential proteins but also on their structural dynamics. the function of these bimolecular systems and the pathways along which the biological phenomena take place can be determined based on the knowledge of the molecular structure and behavior. as such, the simp...

this paper was aimed to report the 3d finite element analysis simulation of laser welding process of ti6al4v 1.7 mm sheets in butt joint in order to predict the temperature distribution, hardness, and weld geometry. the butt-joint welds were made using co2 laser with the maximum power of 2.2 kw in the continuous wave mode. a part of the experimental work was carried out to verify the weld geome...