To an arbitrary directed graph we associate a row-finite directed graph whose Calgebra contains the C-algebra of the original graph as a full corner. This allows us to generalize results for C-algebras of row-finite graphs to C-algebras of arbitrary graphs: the uniqueness theorem, simplicity criteria, descriptions of the ideals and primitive ideal space, and conditions under which a graph algeb...

We study the structure of 0-primitive near-rings and are able to answer an open question in the theory of minimal ideals in near-rings to the negative, namely if the heart of a zero symmetric subdirectly irreducible near-ring is subdirectly irreducible again. Also, we will be able to classify when a simple near-ring with an identity and containing a minimal left ideal is a Jacobson radical near...

Using magnetic composite material as the substrate for RFID metal tag has several advantages over conventional metal tags, such as flexibility and miniaturized size. In this paper, the radiation intensity contributed by a half-wave dipole is derived based on the result of an ideal Hertzian dipole, which leads to a simple relation for thin substrate. Later on, the material constants of two mater...

Authenticated key exchange (AKE) protocol is an important cryptographic primitive that assists communicating entities, who are communicating over an insecure network, to establish a shared session key to be used for protecting their subsequent communication. Lattice-based cryptographic primitives are believed to provide resilience against attacks from quantum computers. An efficient AKE protoco...

We analyze the decomposition rank (a notion of covering dimension for nuclear C-algebras introduced by E. Kirchberg and the author) of subhomogeneous C-algebras. In particular we show that a subhomogeneous C-algebra has decomposition rank n if and only if it is recursive subhomogeneous of topological dimension n and that n is determined by the primitive ideal space. As an application, we use re...

where (a) denotes the two-sided ideal of R generated by a. Then J is the Jacobson radical [6 ] of R, and N is the radical of R as defined in [l]. It is well known that J = 0 if and only if R is isomorphic to a subdirect sum of primitive rings, and ^ = 0 if and only if R is isomorphic to a subdirect sum of simple rings with unit element. The above definitions of / and N suggest that it might be ...

We present a compiler for transforming an oblivious transfer (OT) protocol secure against an adaptive semi-honest adversary into one that is secure against an adaptive malicious adversary. Our compiler achieves security in the universal composability framework, assuming access to an ideal commitment functionality, and improves over previous work achieving the same security guarantee in two ways...

Exploiting the analogy between exemplar models and population coding schemes, we characterize, by means of information theoretic tools, the efficiency of a large but finite population of cells coding for a discrete set of categories (e.g. vowels). The optimal code is shown to typically allocate more cells to class boundaries than to regions further apart. We then discuss the predicted perceptua...

We consider the problem of designing reliable and confidential lattice codes, known as wiretap lattice codes, for fast fading channels. We identify as code design criterion for finite lattice constellations a finite sum of inverse of algebraic norms, in fact the analogous for finite sums of the known criterion for infinite constellations, which motivates us to study totally real number fields w...