Agriculture is one of the pillars of economics and its development requires a particular attention to all production factors. This paper aims to provide a systematic and conceptual model that is based on a conceptualization of the field. For this purpose, the theory and methodology based on data derived from field observations and interviews drawn from a systematic conceptual model of key infor...

many studies concerning persian history have been performed. persian physicians and scientists greatly contributed to medical sciences by their own observations, experimentations and skills through more than seven thousand years of persian history. in persian medieval medicine, different fields were described. among these fields, neurological disorders, especially headache and epilepsy were exp...

morphophysiological variations of field bindweed populations in tehran province was studied during 2006 and 2007 growing seasons using multivariate analysis methods. to determine the variations, 43 morphological and physiological characters were considered biometrically.  the main characters at principal component analysis (pca) consisted of leaf dry weight, shoot dry weight, and leaf area to i...

tectonic processes are major factors controlling landform development in tectonically active areas. in order to evaluate quantitative measurement of tectonic activities in the alamarvdasht basin in the south of iran, six different morphological indices including stream-gradient index (sl), drainage basin asymmetry (af), hypsometric integral (hi), valley floor width-valley height ratio (vf), dra...

in the form of passive seismic methods, broadband seismometers have been used in hydrocarbon exploration. the frequency bandwidth typically studied is in the range of 1–6 hz. the observations on low frequency band of microtremors are used to calculate the spectral ratio of vertical and horizontal components (v/h) and power spectral density (psd). attributes based on the v/h ratio and the psd ha...