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In this paper, we study the $L^p$ boundedness of a class of oscillating multiplier operator for the Dunkl transform, $T_{m_\alpha}=\mathcal{F}_k^{-1}(m_{\alpha}\mathcal{F}_k(f))$ with $m(\xi)=|\xi|^{-\alpha}e^{\pm i|\xi|}\phi(\xi)$. We obtain an $L^p$-bound result for the corresponding maximal functions. As a specific applications, we give an extension of the $L^p$ estimate for the wave equation and of Stein's theorem for the analytic family of maximal spherical means \cite{Stein}, Comment: 18 pages

Agent technology is a software paradigm that permits to implement large and complex distributed applications. In order to assist the development of multi-agent systems, agent-oriented methodologies (AOM) have been created in the last years to support modeling more and more complex applications in many different domains. By defining in a non-ambiguous way concepts used in a specific domain, Meta modeling may represent a step towards such interoperability. In the Transport domain, this paper propose an agent-oriented meta-model that provides rigorous concepts for conducting transportation system problem modeling. The aim is to allow analysts to produce a transportation system model that precisely captures the knowledge of an organization so that an agent-oriented requirements specification of the system-to-be and its operational corporate environment can be derived from it. To this end, we extend and adapt an existing meta-model, Extended Gaia, to build a meta-model and an adequate model for transportation problems. Our new agent-oriented meta-model aims to allow the analyst to model and specify any transportation system as a multi-agent system. Based on the proposed meta-model, we proposes an approach for modeling and evaluating the Transportation System based on Stochastic Activity Network (SAN) components. The proposed process is based on seven steps from Recognition phase to Quantitative Analysis phase. These analyzes are based on the Dependability models which are built using the formalism Stochastic Activity Network. A real case study of Urban Public Transportation System has been conducted to show the benefits of the approach., International Journal of Information Technology, Modeling and Computing (IJITMC) Vol. 2, No. 1, 2014. arXiv admin note: text overlap with arXiv:1204.1581 by other authors without attribution

International audience; In this article, we establish first a geometric Paley-Wiener theorem for the Dunkl transform in the crystallographic case. Next we obtain an optimal bound for the $L^p\to L^p$ norm of Dunkl translations in dimension 1. Finally we describe more precisely the support of the distribution associated to Dunkl translations in higher dimension.

We consider the action of the Lie algebra of polynomial vector fields, $\mathfrak{vect}(1)$, by the Lie derivative on the space of symbols $\mathcal{S}_\delta^n=\bigoplus_{j=0}^n \mathcal{F}_{\delta-j}$. We study deformations of this action. We exhibit explicit expressions of some 2-cocycles generating the second cohomology space $\mathrm{H}^2_{\rm diff}(\mathfrak{vect}(1),{\cal D}_{\nu,\mu})$ where ${\cal D}_{\nu,\mu}$ is the space of differential operators from $\mathcal{F}_\nu$ to $\mathcal{F}_\mu$. Necessary second-order integrability conditions of any infinitesimal deformations of $\mathcal{S}_\delta^n$ are given. We describe completely the formal deformations for some spaces $\mathcal{S}_\delta^n$ and we give concrete examples of non trivial deformations.

The sera of 20 random human heart transplant recipients, drawn before the administration of immunosuppressive medications, were screened for the presence of factors that might inhibit the mixed lymphocyte reaction. The donors for the lymphocyte cultures were unrelated both to one another and to the heart donor and recipient. Inhibition was defined as a reduction of the number of transformed cells produced in vitro to less than one-third of that produced in autologous serum. It appears that patients who have had previous heart surgery on bypass fare better with heart transplants than those who have not had surgery. This may indicate some change in the overall physiology of the former class of patients resulting in better acceptance of the transplant. In turn, this could be due to the development of a serum factor or an impairment in the patients' cellular immune systems. In the series of recipients studied, the majority possessed serum inhibitory factors possibly non-specific by-products of their heart failure. The precise nature of these factors has yet to be determined. Future research is planned to determine whether bypass surgery is responsible for the stimulation of new immuno-depressive factors or if in some way it boosts the titer of pre-existing factors.