in this paper the effects of non-linearity of suspension on dynamic behavior of a railway wheelset has been studied. this wheelset has four degrees of freedom that with two constraints it has reduced to two degrees of freedom. vermeulen-johnson theory has been used to calculate contact forces between wheel and rail. in this study the creep coefficients have considered constant. any linearizatio...

background: the main object of this experimental work was to practise laboratory production both adult and the larval stage of hymenolepis diminuta with conventional modification to make further studies easier. materials & method: adults h. diminuta were collected from urban rats in tehran, iran. the beetles became infected using blended gravid segments with flour as bait. cysticercoids have be...

percentages and yields of fat, crude protein (cp), true protein (tp) and non-protein nitrogen (npn) wereassessed in milk of four groups of holstein cows, at early, mid and late lactation (days in milk 20-70, 71-110, 111-150 and 151-210), on a diet rich in concentrates during a hot summer. four milk samples were taken from individual cows at 10-day intervals. milk fat percentages were close to b...

the aim of this study was to evaluate the defense cells changes of cervical mucous during follicular and luteal phases of estrus cycle in river buffalo. reproductive organs of the adult and apparently healthy female buffaloes were collected from the slaughterhouse. by visual investigation of both the ovaries for presence of corpus luteum and growing follicles, the luteal and follicular phase of...

to investigate uterine and serum ca++ and mg++ variations during the estrous cycle in the bovine, 66 genital tracts and blood samples were collected from urmia abattoir, urmia, iran. the phase of the estrous cycle was determined by examination of the structures present on ovaries and uterine tonicity. of the collected samples, 17 were pro-estrus, 12 estrus, 14 metestrus and 23 diestrus. the ute...

there are many claims that quantum mechanics plays a key role in the origin and/or operation of biological organisms. the mechanism of the meiosis, mitosis and gametes life cycle from the view-point of quantum for human has been represented. the quantum gates have been used to simulate these processes for the first time. the reason of several hundred sperms has been explained in the male too

in this paper, a multi-objective method is used to optimize a heat recovery steam generator (hrsg). two objective functions have been used in the optimization, which are irreversibility and hrsg equivalent volume. the former expresses the exergetic efficiency and the latter demonstrates the cost of the hrsg. decision variables are geometric and operational parameters of the hrsg. the results of...

in this study the reproductive organs of adult and apparently healthy female azarbaijan buffaloes werecollected after slaughter from abattoir. through observation of the ovaries, the luteal and follicular phases ofeach buffalo were specified. a total number of 36 oviducts at follicular phase and 36 oviducts at luteal phasewere collected and 3 tissue samples were taken from 3 regions of infundib...