Horizontal wellswith multi-cluster fracturing technology is an effective approach to exploit unconventional hydrocarbon reservoirs. The on-site diagnosis results indicate that fractures always tend propagate unevenly due stressinterference, therefore it very essential study the effect of parameters on fracture propagation unevenness. In this paper, model (UFM, Unconventional Fracturing Model) u...

these are notes from introductory survey lectures given at the institute for studies in theoretical physics and mathematics (ipm), teheran, in 2008 and 2010. we present the definition and the fundamental properties of fomin-zelevinsky’s cluster algebras. then, we introduce quiver representations and show how they can be used to construct cluster variables, which are the canonical generators of ...

the genetic variation and population structure of narrow-clawed crayfish (astacus leptodactylus) was examined by means of polymerase chain reaction (pcr) restriction fragment length polymorphism (rflp) analysis of the cytochrome oxidase subunit i (coi) of mitochondrial dna. a total of 194 adult specimens were collected from seven sample sites including, two in the south caspian sea and one each...

abstract an investigation was performed in a commercial orchard in shiraz to study the effect of time of application of cuso4 and streptomycin on quality and seedlessness of grapevine (vitis vinifera l. cv. ‘siyah-e-shiraz’). the experiment was conducted as completely randomized block design with 3 replications. plants were treated with 25 mgl-1 cuso4. 5h2o and 200mgl-1 streptomycin 2,4 and 6 d...

Objective: Yield components and genetic contribution have the most important in final yield and breeding programs of crop plants. For this purpose, 20 varieties of grapevines with Russia origin were evaluated in Urmia and Takestan research station (under full irrigation and drought stress). Methods: Twenty grapevine genotypes were evaluated in Urmia and Takestan research station (under full irr...

Existing exact results for the percolation probability and mean cluster size for compact percolation near a dry wall are extended to the mean cluster length and the mean number of contacts with the wall. The results are derived from our previous work on vesicles near an attractive wall and involve elliptic integrals as opposed to the simple rational forms found for the percolation probability a...