0 7 4 0 7 4 5 9 / 0 0 / $ 1 0 . 0 0 © 2 0 0 0 I E E E ground. We agree with F.G. Harold’s concept of “optimal heterophily”1 and use the term software engineering to include information technology. Y2K presented a formidable (albeit welldefined) challenge: find the date problems and fix them (see our “Congratulations” in the accompanying sidebar). Post-Y2K presents a more formidable challenge: a...

Image transmission with JPEG2000 can be speeded up by using regions of interest (RoIs). By such a mechanism, parts of an image not belonging to RoIs can be transmitted later or encoded at a lower bit rate. This paper describes a flexible dynamic RoI-scheme which supports the definition and handling of arbitrarily-shaped RoIs in JPEG2000. The scheme supports the dynamic definition and prioritiza...

Mainstream Information Technology professionals have misunderstood the Pick environment for many years. The Pick environment has been conceived, designed and built with business solutions as its key driver. At its heyday there were over 3,000 business applications available across a very wide range of hardware platforms supporting from 1 to thousands of real time users. The tentative economic r...

With the increasing use of multimedia technologies, image compression requires higher performance as well as new features. To address this need in the speci®c area of still image encoding, a new standard is currently being developed, the JPEG2000. It is not only intended to provide rate-distortion and subjective image quality performance superior to existing standards, but also to provide funct...

The human visual system plays a key role in the final perceived quality of the compressed images. It is therefore desirable to allow system designers and users to take advantage of the current knowledge of visual perception and models in a compression system. In this paper, we review the various tools in JPEG-2000 that allow its users to exploit many properties of the human visual system such a...

Resumo. Organizações têm sido cobradas por sua capacidade de fornecer informações sobre seu funcionamento e resultados. Porém tornar-se transparentes não é apenas divulgar informações, é necessário que estas informações sejam tratadas, usadas e compreendidas por seu público alvo. Este artigo descreve uma proposta de evolução de um Catálogo de Transparência, com um estudo mais aprofundado sobre ...

Let f(x) ∈ Z[x] be a totally real polynomial with roots α1 ≤ . . . ≤ αd. The span of f(x) is defined to be αd − α1. Monic irreducible f(x) of span less than 4 are special. In this paper we give a complete classification of those small-span polynomials which arise as characteristic polynomials of integer symmetric matrices. As one application, we find some low-degree polynomials that do not aris...

Resumo. Estabelecer modelos de determinado domínio é um dos princípios básicos para uma construção de software com qualidade. Estes modelos facilitam a compreensão de realidades complexas, seus detalhes e interações de suas partes. Entre várias características, a Engenharia de Requisitos Orientada a Metas (GORE) sugere a modelagem de objetivos para expressar a razão das necessidades dos requisi...

This study was undertaken to assess both the relation between echocardiographic measurement of left ventricular (LV) mass and commonly used electrocardiographic criteria for LV hypertrophy and the effect of the distance from the center of LV mass to the anterior chest wall on precordial voltage. Echocardiograms and standard 12-lead electrocardiograms were obtained on 100 persons, ages 3 to 79. ...

Este artigo investiga, teoricamente, a dinâmica de um modelo de membrana sob estimulação elétrica externa. Este sistema mostra vários tipos de respostas oscilatórias no potencial da membrana, quando uma corrente sinoidal AC é superposta à corrente DC aplicada através da membrana. À medida que a frequência da corrente AC varia, este comportamento varia de oscilações periódicas, P1, até oscilaçõe...