Software assurance practices for mobile applications

Mobile software applications have to cope with a particular environment that involves small size, limited resources, high autonomy requirements, competitive business models and many other challenges. To provide development guidelines that respond to these needs, several practices have been introduced; however, it is not clear how these guidelines may contribute to solve the issues present in the mobile domain. Furthermore, the rapid evolution of the mobile ecosystem challenges many of the premises upon which the proposed practices were designed. In this paper, we present a survey of the literature on software assurance practices for mobile applications, with the objective of describing them and assessing their contribution and success. We identified, organized and reviewed a body of research that spans in three levels: software development processes, software product assurance practices, and software implementation practices. By carrying out this literature survey, we reviewed the different approaches that researchers on Software Engineering have provided to address the needs that raise in the mobile software development arena. Moreover, we review the evolution of these practices, identifying how the constant changes and modernization of the mobile execution environment has impacted the methods proposed in the literature. Finally, we introduced discussion on the application of these practices in a real productive setting, opening an area for further research that may determine if practitioners have followed the proposed assurance paradigms.     

Path dependent stochastic models to detect planned and actual technology use: A case study of OpenOffice

Context

Adopting IT innovation in organizations is a complex decision process driven by technical, social and economic issues. Thus, those organizations that decide to adopt innovation take a decision of uncertain success of implementation, as the actual use of a new technology might not be the one expected. The misalignment between planned and effective use of innovation is called assimilation gap.

Objective

This research aims at defining a quantitative instrument for measuring the assimilation gap and applying it to the case of the adoption of OSS.

Method

In this paper, we use the theory of path dependence and increasing returns of Arthur. In particular, we model the use of software applications (planned or actual) by stochastic processes defined by the daily amounts of files created with the applications. We quantify the assimilation gap by comparing the resulting models by measures of proximity.

Results

We apply and validate our method to a real case study of introduction of OpenOffice. We have found a gap between the planned and the effective use despite well-defined directives to use the new OS technology. These findings suggest a need of strategy re-calibration that takes into account environmental factors and individual attitudes.

Conclusions

The theory of path dependence is a valid instrument to model the assimilation gap provided information on strategy toward innovation and quantitative data on actual use are available.     

On the small-scale dynamical behavior of lattice BGK and lattice Boltzmann schemes

In this paper, we report some comparative simulations between lattice BGK and lattice Bolzmann schemes for two-dimensional fluid flows. A quantitative assessment of the validity of the lattice BGK and lattice Bolzmann schemes is presented for the two-dimensional weakly compressibleKolmogorov flow. We use this flow to study the difference of the two schemes at small scales. A lowReynolds (R _e 300) number simulation shows the almost identical energy spectra for both schemes except for the small-scale dynamics of lattice Bolzmann which is more noisy. Because of the intrinsic difficulties of nonlinear stability analysis, we use numerical simulations to investigate which scheme is more stable. It turns out the lattice BGK is more stable. It turns out the lattice BGK is more robust than lattice Bolzmann by increasing theReynolds numbers. Detailed comparison with other methods (e.g., spectral method) remains to be done in the near future.     

Project management in plan-based and agile companies

Agile methods are a recent set of development techniques that apply a human-centered approach to software production. The agile approach aims to deliver high-quality products faster, producing satisfied customers. We conducted an empirical study to investigate whether agile methods change and improve project management practices in software companies. Survey results show that adopting agile methods appears to improve management of the development process and customer relationships. This article has given a first analysis of the advantages and disadvantages of adopting agile methods from a project management perspective.     

Parallel efficiency of the C.R.F. method on an IBM RS/6000 cluster platform

A new numerical method for kinetic equations in several dimensions has been recently presented by Motta and Wick (1991). The method has been then applied to simple models to test its applicability to realistic physical situations. In the present paper we discuss the parallel performance of the method on a distributed memory platform based on a cluster of IBM RS/6000 superscalar workstations.     

Atomic absorption evaporation flow rate measurements of alkali metal dispensers

The preparation of photosensitive surfaces in phototubes is generally perfoemed with alkali metal dispensers (AMDs). Since a very well controlled evaporation flow rate of the alkali vapours released from AMDs are of great importance, a method based on the atomic absorption technique, has been developed for its accurate measurement. This method can overcome some limitations of other methods such as those based on the work function change of cathodes in the presence of alkali vapours. The test AMD is mounted in a specifically designed glass cell which is evacuated and baked overnight at 350°C to have a residual pressure in the range of 10^?6 Pa. The cell is provided with a Ba getter to ensure a good vacuum, essential for the application of this technique, and with an Sb generator to capture the alkali metal vapour. After tip-off, the cell is mounted on the atomic absorption spectrophotometer in the burner position. An absorption signal is generated by the alkali atoms released by the AMD, when they intercept a monochromatic light beam resonant with the alkali metal. With an appropriate calibration the absorption signal can be converted into evaporation flow rate. This technique has been applied to the study of caesium generators and practical results are given. The sensitivity of the method is a flow of about 1 μg min^?1.     

Digital Physics Simulations of Reactive Flow in a Catalytic Converter

We describe the basic ideas behind the extension of the Digital Physics paradigm to include reactive flow capabilities. An application to catalytic conversion is presented.     

Endothelial shear stress from large-scale blood flow simulations

We discuss the optimal evaluation of endothelial shear stress for real-life case studies based on anatomic data acquisition. The fluid dynamic simulations require smoothing of the geometric dataset to avoid major artefacts in the flow patterns, especially in the proximity of bifurcations. A systematic series of simulations at different corrugation levels shows that, below a smoothing length of about 0.5 mm, the numerical data are insensitive to further smoothing.     

A four-color parallel algorithm for the solution of a two-dimensional advection-diffusion equation with the finite element method

Reordering schemes associated with multicoloring and domain decomposition techniques have been introduced in recent years to obtain parallel and/or vectorized versions of recursive linear solvers such as the Gauss-Seidel SOR scheme (Ortega and Voigt, 1986; White, 1989). In this paper we give a brief account of the successfull implementation of a four-color Gauss-Seidel parallel algorithm for the solution of block-tridiagonal matrices resulting from the finite-element discretization of a two-dimensional advection-diffusion equation. Performance data referring to the implementation on the IBM 3090/400 vector multiprocessor are reported and commented on.