Let S be an ordered semigroup. In this paper we first introduce the concepts of (∈,∈ ∨qk)-fuzzy ideals, (∈,∈ ∨qk)-fuzzy bi-ideals and (∈,∈ ∨qk)-fuzzy generalized bi-ideals of an ordered semigroup S by the ordered fuzzy points of S, and investigate their related properties. Furthermore, characterizations of regular ordered semigroups by the properties of (∈,∈ ∨qk)-fuzzy left ideals, (∈,∈ ∨qk)-fu...

In this paper, we introduce the notion of hyper pseudo B C K - algebras, which is a generalization of pseudo BCK -algebras and hyper BCK -algebras and we investigates some related properties. In follow, we de ne some kinds of hyper pseudo BCK -ideals of a hyper pseudo BCK - algebra and we find the relations among them. Finally, we characterize the hyper pseudo BCK -ideals of type 4 generated by...

Bi ideals are the generalization of quasi ideals which are themselves the generalization of the so called one-sided, right and left ideals. In this paper, we define the m-bi ideals as a generalization of the bi ideals. The important properties of the m-bi ideals from the pure algebraic point of view have been described. Moreover, we present the form of the m-bi ideals generated by subsets of th...

Various questions on Lie ideals of C∗-algebras are investigated. They fall roughly under the following topics: relation of Lie ideals to closed two-sided ideals; Lie ideals spanned by special classes of elements such as commutators, nilpotents, and the range of polynomials; characterization of Lie ideals as similarity invariant subspaces.

Perfectionism can be mentally costly for people who deviate from selfimposed norms of behavior. I model perfectionism in Gul and Pesendorfer’s (2001) framework where agents can be tempted by immediate consumption. Besides normative and temptation utilities, my model identifies a mental cost of perfectionism that is proportional to the difference between the decision maker’s actual choices and h...

This solution set was written by Pokman; Ravi has added some comments and hopefully hasn’t introduced too many errors! 1. Show that a ring in which all ideals are finitely generated cannot have an infinite sequence of ideals Conversely, show that if a ring has no infinite sequence of ideals, then all ideals are finitely generated. Solution. Suppose all ideals of a ring are finitely generated, a...