On extremal intersection numbers of a block design

Block Intersection Numbers of Block Designs Ii

Intersection Numbers of Extremal Rays on Holomorphic Symplectic Varieties

Suppose X is a smooth projective complex variety. Let N1(X,Z) ⊂ H2(X,Z) and N (X,Z) ⊂ H(X,Z) denote the group of curve classes modulo homological equivalence and the Néron-Severi group respectively. The monoids of effective classes in each group generate cones NE1(X) ⊂ N1(X,R) and NE (X) ⊂ N(X,R) with closures NE1(X) and NE 1 (X), the pseudoeffective cones. These play a central rôle in the bira...

On Kelley’s Intersection Numbers

We introduce a notion of weak intersection number of a collection of sets, modifying the notion of intersection number due to J.L. Kelley, and obtain an analogue of Kelley’s characterization of Boolean algebras which support a finitely additive strictly positive measure. We also consider graph-theoretic reformulations of the notions of intersection number and weak intersection number. Kelley [4...

a study on the design of bio-ethanol process from date wastes of sistan and baluchistan province

اتانول کاربردهای متنوعی در صنایع لاستیک سازی، رنگسازی، حلالها ومکمل سوخت خودرو دارد. اتانول برخلاف نفت از جمله مواد تجدیدپذیر محسوب می شود که مشکلات زیست محیطی و آلودگی نیز ایجاد نمی کند. استفاده از اتانول به عنوان مکمل سوختخودروها از جمله مهمترین مصارف صنعتی این ماده بشمار می رود. با توجه به این موضوع تحقیق و توسعه در زمینه تولید اتانول با درجه خلوص بالا در سطح جهان، و نه تنها در کشور های پیشر...

On the structure of 1-designs with at most two block intersection numbers

We introduce the notion of an unrefinable decomposition of a 1-design with at most two block intersection numbers, which is a certain decomposition of the 1-designs collection of blocks into other 1-designs. We discover an infinite family of 1-designs with at most two block intersection numbers that each have a unique unrefinable decomposition, and we give a polynomial-time algorithm to compute...