A DHCP-based IP address autoconfiguration for MANETs

Mobile Ad hoc Networks (MANETs) are expected to become more and more important in the upcoming years, playing a significant role in 4G networks. In order to enable the deployment of IP services in such networks, IP address autoconfiguration mechanisms are required. Although the ad hoc topic has been a very intense research area, with a plethora of published papers about routing, there is a lack of proposals of address autoconfiguration with enough support from the technical community. This paper presents a mechanism suited for MANETs connected to the Internet, reusing existing and widely deployed address autoconfiguration protocols, such as DHCPv6 and Router Advertisements

Performance of active multicast congestion control

This paper aims to provide insight into the behavior of congestion control mechanisms for reliable multicast protocols. A multicast congestion control based on active networks has been proposed and simulated using ns-2 over a network topology obtained using the Tiers tool. The congestion control mechanism has been simulated under different network conditions and with different settings of its configuration parameters. The objective is to analyze its performance and the impact of the different configuration parameters on its behavior. The simulation results show that the performance of the protocol is good in terms of delay and bandwidth utilization. The compatibility of the protocol with TCP flows has not been demonstrated, but the simulations performed show that by altering the parameter settings, the proportion of total bandwidth taken up by the two types of flow, multicast and TCP, may be modified.Publicad

Operators with dense images everywhere

In this paper, the authors introduce the dense-image operators T as those with a wild behaviour near of the boundary of a domain G, via certain subsets. The relationship with other kinds of operators with wild behaviour is studied, proving that the new concept generalizes the earlier of omnipresent, but there is no good relationship with the strongly omnipresent operators. We obtain, among other results, that the following kinds of operators are dense-image: onto linear operators; operators with local dense range satisfying soft conditions; Volterra complex integral operators plus infinite order differential operators, multiplication operators. In addition, holomorphic selfmappings and entire functions generating dense-image right or left composition operators are completely characterized.Dirección General de Enseñanza Superior (DGES). EspañaJunta de Andalucí

Monsters in Hardy and Bergman spaces

A monster in the sense of Luh is a holomorphic function on a simply connected domain in the complex plane such that it and all its derivatives and antiderivatives exhibit an extremely wild behaviour near the boundary. In this paper the Hardy spaces Hp and the Bergman spaces Bp (1 ≤ p < ∞) on the unit disk are considered, and it is shown that there are no Luh-monsters in them. Nevertheless, it is proved that T-monsters (as introduced by the authors in an earlier work) can be found in each of these spaces for any finite order linear differential operator T.Plan Andaluz de Investigación (Junta de Andalucía

A Seidel-Walsh theorem with linear differential operators

Assume that {Sn}∞1 is a sequence of automorphisms of the open unit disk D and that {Tn}∞1 is a sequence of linear differential operators with constant coefficients, both of them satisfying suitable conditions. We prove that for certain spaces X of holomorphic functions in the open unit disk, the set of functions f ∈ X such that {(Tnf) ◦ Sn : n ∈ N} is dense in H(D) is residual in X. This extends the Seidel-Walsh theorem together with some subsequent results.Dirección General de Enseñanza Superior (DGES). EspañaJunta de Andalucí

Large algebras of singular functions vanishing on prescribed sets

In this paper, the non-vacuousness of the family of all nowhere analytic infinitely differentiable functions on the real line vanishing on a prescribed set Z is characterized in terms of Z. In this case, large algebraic structures are found inside such family. The results obtained complete or extend a number of previous ones by several authors.Comment: 11 page

Hypercyclic algebras for D-multiples of convolution operators

It is shown in this short note the existence, for each nonzero member of the ideal of D-multiples of convolution operators acting on the space of entire functions, of a scalar multiple of it supporting a hypercyclic algebra.Plan Andaluz de Investigación (Junta de Andalucía)Ministerio de Economía y Competitividad (MINECO). Españ

Private benefits extraction in closely-held corporations: the case for multiple large shareholders

This paper investigates how multiple large shareholders share control and extract private benefits in closely-held corporations. We find that ownership structures with multiple large shareholders are common and very stable. Moreover, they seem to be, to a large extent, exogenously given. The structure of the controlling group of shareholders has a very significant impact on performance. Performance improves as the control group's ownership stake increases and, for a given ownership stake, as the number of members increases. The economic significance of the effects indicates that minority expropriation is a very important problem in closely-held firms

Boundary-chaotic behaviour of continuous functions under the action of operators

In this paper we introduce two classes of operators on spaces of continuous functions with values in F-spaces under the action of which many functions behave chaotically near the boundary. Several examples, including onto linear operators, left and right composition operators, multiplication operators, and operators with pointwise dense range or with some stability property, are given. This new theory extends one recently developed on spaces of holomorphic functions.Plan Andaluz de Investigación (Junta de Andalucía

Dense linear manifolds of monsters

In this paper the new concept of totally omnipresent operators is introduced. These operators act on the space of holomorphic functions of a domain in the complex plane. The concept is more restrictive than that of strongly omnipresent operators, also introduced by the authors in an earlier work, and both of them are related to the existence of functions whose images under such operators exhibit an extremely wild behaviour near the boundary. Sufficient conditions for an operator to be totally omnipresent as well as several outstanding examples are provided. After extending a statement of the first author about the existence of large linear manifolds of hypercyclic vectors for a sequence of suitable continuous linear mappings, it is shown that there is a dense linear manifold of holomorphic monsters in the sense of Luh, so completing earlier nice results due to Luh and Grosse-Erdmann.Dirección General de Enseñanza Superior (DGES). EspañaJunta de Andalucí