background: the goal was to upgrade and/or uprate the traditional non-contact array by producing few modifications in the configuration of this model in order to maximize light receiving of water from the uv lamp and a better disinfection.  methods: an innovative non-contact model was made with a design based on irradiation of water, which was flowing as two thin waterfalls around a uv lamp in ...

background: despite their simplicity and the low-cost, the conventional non-contact uv systems have low efficiency in water disinfection. the purpose of this study was to examine the possibility of upgrading these systems by some modifications in order to maximize the water contact with the uv radiation and as a result a better disinfection.    methods: in this study, two enhanced models of non...

Everyone knows that the waterfall life cycle model suffers from a number of problems but in spite of this, it continues to be the most widely used life cycle model. This paper argues that many of these problems stem from project management best practices that are inappropriately applied in the waterfall model. A different life cycle approach is proposed that emphasise the product life cycle rat...

The traditional waterfall life cycle has been the mainstay for software developers for many years. For software products that do not change very much once they are specified, the waterfall model is still viable. However, for software products that have their feature sets redefined during development because of user feedback and other factors, the traditional waterfall model is no longer appropr...

The applicability of the waterfall model was tested using the Starling resistor and different viscosities of fluids to vary the Reynolds number. The waterfall model proved adequate to describe flow in the Starling resistor model only at very low Reynolds numbers (Reynolds number less than 1). Blood flow characterized by such low Reynolds numbers occurs only in the microvasculature. Thus, it is ...

The need for a formal development structure to produce high quality software products was addressed in 1970 when Royce described the initial software lifecycle model, the now classic Waterfall model. Building on the initial Stepwise model, the Waterfall model was to be re-introduced in a landmark article1, giving it a world-wide audience and adopting it as the conventional lifecycle model. The ...

Agile methods have emerged and become popular over last few years as a response to shortcomings of the waterfall process model. However, agile processes are stamped by some as chaotic processes and are placed in opposition to waterfall approaches. This paper uses the edge of chaos concept from complex adaptive systems theory as a theoretical lens to analyse the roles of structure and planning i...

Growth is one of the most compelling goals of managers today. This paper addresses the following questions about the international growth of new products in Europe: Does the pattern of growth differ across countries? If so, does culture or economics explain the differences? What are the implications of these results for new product strategy? The results show that the pattern of growth differs s...

We propose a hybrid inflation model with a complex waterfall field which contains an interaction term that breaks the U(1) global symmetry associated with the waterfall field charge. We show that the asymmetric evolution of the real and imaginary parts of the complex field during the phase transition at the end of inflation translates into a charge asymmetry. The latter strongly depends on the ...

0 7 4 0 7 4 5 9 / 0 3 / $ 1 7 . 0 0 © 2 0 0 3 I E E E complement the waterfall model, others appear to contradict its main principles. Furthermore, the performance dimensions that each practice seeks to optimize often differ. Unfortunately, these potential conflicts are difficult to resolve because the data presented to support most models is anecdotal and biased toward reporting only successfu...