Fast Hybrid Computational Technique for the Analysis of Radome Structures Using Dual Domain Decomposition

This work details a technique tailored to the analysis of complex radome structures based on the non-overlapping separation of two different domains: antenna and radome. Both domains are analyzed isolated using the method of moments with the multilevel fast multipole algorithm (MoM-MLFMA) for the antenna domain and a modified characteristic basis function method with the multilevel fast multipole algorithm approach for the radome domain. An iterative procedure is then applied to compute the effect of each domain over the complementary domain. This approach usually converges into a few iterations, yielding very good results and significant efficiency improvements with respect to other efficient approaches such as a full-wave MoM-MLFMA analysis of the full problem. A realistic test case is included, considering a radome with an embedded frequency selective structure on one of its interfaces. The results show a very good agreement considering only three iterations between domains, requiring only one-third of the CPU-time needed by the conventional approach.

Strategies and cognitive reserve to preserve lexical production in aging

In the absence of any neuropsychiatric condition, older adults may show declining performance in several cognitive processes and among them, in retrieving and producing words, reflected in slower responses and even reduced accuracy compared to younger adults. To overcome this difficulty, healthy older adults implement compensatory strategies, which are the focus of this paper. We provide a review of mainstream findings on deficient mechanisms and possible neurocognitive strategies used by older adults to overcome the deleterious effects of age on lexical production. Moreover, we present findings on genetic and lifestyle factors that might either be protective or risk factors of cognitive impairment in advanced age. We propose that “aging-modulating factors” (AMF) can be modified, offering prevention opportunities against aging effects. Based on our review and this proposition, we introduce an integrative neurocognitive model of mechanisms and compensatory strategies for lexical production in older adults (entitled Lexical Access and Retrieval in Aging, LARA). The main hypothesis defended in LARA is that cognitive aging evolves heterogeneously and involves complementary domain-general and domain-specific mechanisms, with substantial inter-individual variability, reflected at behavioral, cognitive, and brain levels. Furthermore, we argue that the ability to compensate for the effect of cognitive aging depends on the amount of reserve specific to each individual which is, in turn, modulated by the AMF. Our conclusion is that a variety of mechanisms and compensatory strategies coexist in the same individual to oppose the effect of age. The role of reserve is pivotal for a successful coping with age-related changes and future research should continue to explore the modulating role of AMF.

The IT Architecture Dimension

The main purpose of this chapter is to present some important aspects of a complementary domain of the concept of architecture: the Information Technology (IT) dimension of the enterprise, or its “IT architecture.” There are several ways to reveal the elements and importance of information and communication technologies (the application of computers and telecommunications equipment to store, retrieve, transmit, and manipulate data, often in the context of a business or other enterprise). A simple and straight description is offered by Englander (2009). Therefore, a proper understanding of the concept of IT architecture as a complement of the corporate dimension is what this chapter is about.

SOME IMBEDDING THEOREMS AND THE SOLVABILITY OF THE SYSTEM OF HYPERBOLIC-PARABOLIC EQUATIONS

A number of physical problems is described by a system of first order hyperbolic equations in a subregion of the physical domain, and of parabolic equations in the complementary domain. To state these problems correctly an investigation of the existence of the trace for a function which possesses a weak derivative in some direction is needed. This problem is solved in the paper. Also we formulate the problem for hyperbolic-parabolic equations (including the description of the transmission condition on the internal boundary), then we prove its solvability.

The Behaviour of Meromorphic Functions with a Set of Singularities of the Class N0B

Let E be a totally disconnected compact set in the complex z-plane and let G be the complementary domain of E with respect to the extended z-plane. Consider a domain in G whose relative boundary consists of at most a countable number of analytic curves clustering nowhere in G. Such a domain is called a subregion in G.