A large class of Type II fluid solutions to Einstein field equations in Ndimensional spherical spacetimes is found, wich includes most of the known solutions. A family of the generalized collapsing Vaidya solutions with homothetic self-similarity, parametrized by a constant λ, is studied, and found that when λ > λc(N), the collapse always forms black holes, and when λ < λc(N), it always forms n...

in this paper, we introduce hybrid of block-pulse functions and bernstein polynomials and derive operational matrices of integration, dual, differentiation, product and delay of these hybrid functions by a general procedure that can be used for other polynomials or orthogonal functions. then, we utilize them to solvedelay differential equations and time-delay system. the method is based upon ex...

We specifv and estimate an equilibrium job search model with pro” ductivitv differences across labor market segments. The model allows for two types of unemployment: frictional unemployment due to search frictions and structural unemployment due to wage floors. Wage floors exist because of high unemplovment benefits or binding minimum wages. The . productivitv distribution is estimated semi-non...

Let us review the fundamental framework of streaming. Suppose we have a stream coming in from time 0 to time T . At each time t ∈ [T ], the coming element is at ∈ [n]. Frequency for any element i is defined as mi = |{j|aj = i}|. We will see a few problems to solve under this framework. For different problems, we expect to have a complexity of only O(log n) and O(log T ) on either storage or upd...

Nowadays, ontology is applied as an integral part of many applications in several domains, especially in the world of law. The ontology based judicial support system is believed as a useful tool to support, for example, the legal argumentation assistant and legal decision taking in court. The privacy case analyzer is considered as one of the most interesting applications of ontology based priva...

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To date there has been limited published work in the construction management and engineering literature that has provided empirical evidence to demonstrate that IT can improve organizational performance. Without an explicit understanding about how IT can be effectively used to improve organizational performance, its justification will remain to be weak for managers. To ensure the continuous inc...

Eichler integrals play an integral part in the modular parametrizations of elliptic curves. In her master’s thesis, Kodgis conjectures several dozen zeros of Eichler integrals for elliptic curves with conductor ≤ 179. In this paper we prove a general theorem which confirms many of these conjectured zeros. We also provide two ways to generate infinite families of elliptic curves with certain zer...

A robot-vision project is reported which incorporates several existing AI methods and some new results. The ambition of the project is a system which can economically complete various intelligent tasks within the scope of mi~and microcomputers. The tuned composition of the applied methods provides a new and powerful approach to Rand D engineering and workshop-operation.