Weak factorization systems Weak factorization systems are of paramount importance to homotopical algebra. This connection is best illustrated by the following definition, due to Joyal and Tierney [JT07]. Definition 1. A Quillen model structure on a category M, with a class of maps W called weak equivalences satisfying the 2-of-3 property, consists of two classes of maps C and F so that (C ∩W,F)...

The present work relates to the antenna design for mobile terminals. It’s about PIFA antennas (Planar InvertedFAntenna). The modification of the certain existing structures geometrical forms allowed the operation of those according to current standards. The design is performed by using the SuperNEC and HFSS simulators. The conception of four antennas: broadband, Bi-band, tri-band and quadriband...

Let X be a non-singular projective threefold over an algebraically closed field of any characteristic, and let A(X) be the group of algebraically trivial codimension 2 algebraic cycles on X modulo rational equivalence with coefficients in Q. Assume X is birationally equivalent to another threefold X ′ admitting a fibration over an integral curve C whose generic fiber X ′ η̄, where η̄ = Spec(k(C))...

a concept of weak $f$-property for a set-valued mapping is introduced‎, ‎and then under some suitable assumptions‎, ‎which do not involve any information‎ ‎about the solution set‎, ‎the lower semicontinuity of the solution mapping to‎ ‎the parametric‎ ‎set-valued vector equilibrium-like problems are derived by using a density result and scalarization method‎, ‎where the‎ ‎constraint set $k$...

Given an infinite Boolean algebra B, we find a natural class of ∅-definable equivalence relations EB such that every imaginary element from B is interdefinable with an element from a sort determined by some equivalence relation from EB . It follows that B together with the family of sorts determined by EB admits elimination of imaginaries in a suitable multisorted language. The paper generalize...

An integer additive set-indexer is defined as an injective function f : V (G) → 2N0 such that the induced function gf : E(G) → 2N0 defined by gf (uv) = f(u) + f(v) is also injective, where f(u) + f(v) is the sumset of f(u) and f(v). If gf (uv) = k ∀ uv ∈ E(G), then f is said to be a k-uniform integer additive set-indexers. An integer additive set-indexer f is said to be a weak integer additive ...

What is a qualitative calculus? Many qualitative spatial and temporal calculi arise from a set of JEPD (jointly exhaustive and pairwise disjoint) relations: a stock example is Allen’s calculus, which is based on thirteen basic relations between intervals on the time line. This paper examines the construction of such a formalism from a general point of view, in order to make apparent the formal ...

Traditionally, syllogisms are arguments with two premises and one conclusion which are constructed by propositions of the form “All... are...” and “At least one... is...” and their respective negated versions. Unfortunately, the practical use of traditional syllogisms is quite restricted. On the one hand, the “All...” propositions are too strict, since a single counterexample suffices for falsi...

We investigate the problem of the stability of the number of conjugate or focal points (counted with multiplicity) along a semi-Riemannian geodesic γ. For a Riemannian or a non spacelike Lorentzian geodesic, such number is equal to the intersection number (Maslov index) of a continuous curve with a subvariety of codimension one of the Lagrangian Grassmannian of a symplectic space. Such intersec...

This is a paper in a series to study vertex algebra-like structures arising from various algebras including quantum affine algebras and Yangians. In this paper, on the basis of [Li6] we develop a theory of (weak) quantum vertex F((t))-algebras with F a field of characteristic zero and t a formal variable, and we give a general construction of (weak) quantum vertex F((t))-algebras and their modu...