Architectural styles and patterns play an important role in software engineering. One of the most known ones is the layered architecture style. However, this style is usually only stated informally, which may cause problems such as ambiguity, wrong conclusions, and difficulty when checking the conformance of a system to the style. We address these problems by providing a formal, denotational se...

any software libraries have been created to support the commonly used primitive operations needed in image processing, image analysis and image understanding. Generally, these libraries Mar e based on the single-layered Application Program Interface (API). While a single-layered API provides the useful abstraction level to interact with the library and hides unnecessary implementation details f...

Layered learning is a hierarchical machine learning paradigm that enables learning of complex behaviors by incrementally learning a series of sub-behaviors. A key feature of layered learning is that higher layers directly depend on the learned lower layers. In its original formulation, lower layers were frozen prior to learning higher layers. This article considers a major extension to the para...

Layered defenses are necessary for protecting the public from terrorist attacks. Designing a system of such defensive measures requires consideration of the interaction of these countermeasures. In this article, we present an analysis of a layered security system within the lower Manhattan area. It shows how portfolios of security measures can be evaluated through portfolio decision analysis. C...

A fundamental goal of research in the perception of surfaces is to understand the nature of the computations and representations underlying lightness perception. A significant challenge posed to the visual system is recovering surface lightness from the multiple physical causes that contribute to image luminance. One view asserts that the visual system decomposes the image into estimates of ill...

In this paper, we investigate the use of layered spacetime scheme, known as V-BLAST, for multiuser detection over the uplink of a DS/CDMA communication system. The multiple transmit antennas in V-BLAST are treated as individual mobile station transmitters, while the base station consists of multiple receive antennas. The layered space-time algorithm is then invoked to detect the signals from al...

A simple model of the dynamics of flaws within a software security system is presented. We demonstrate how this model can be fully captured by a Galton-Watson branching process and thus can be effectively calculated upon. Using the limit behaviour of a Galton-Watson branching process, we can demonstrate how a multi-layered security system can become secure even with ’poor’ flaw correction. Fina...

We propose a method for visualizing a set of related metabolic pathways across organisms using 2 1/2 dimensional graph visualization. Interdependent, twodimensional layouts of each pathway are stacked on top of each other so that biologists get a full picture of subtle and significant differences among the pathways. The (dis)similarities between pathways are expressed by the Hamming distances o...

introduction lead-based shields are the most widely used attenuators in x-ray and gamma ray fields. the heavy weight, toxicity and corrosion of lead have led researchers towards the development of non-lead shields. materials and methods the purpose of this study was to design multi-layered shields for protection against x-rays and gamma rays in diagnostic radiology and nuclear medicine. in this...