A Case Study on Artefact-based RE Improvement in Practice

Most requirements engineering (RE) process improvement approaches are solution-driven and activity-based. They focus on the assessment of the RE of a company against an external norm of best practices. A consequence is that practitioners often have to rely on an improvement approach that skips a profound problem analysis and that results in an RE approach that might be alien to the organisational needs. In recent years, we have developed an RE improvement approach (called \emph{ArtREPI}) that guides a holistic RE improvement against individual goals of a company putting primary attention to the quality of the artefacts. In this paper, we aim at exploring ArtREPI's benefits and limitations. We contribute an industrial evaluation of ArtREPI by relying on a case study research. Our results suggest that ArtREPI is well-suited for the establishment of an RE that reflects a specific organisational culture but to some extent at the cost of efficiency resulting from intensive discussions on a terminology that suits all involved stakeholders. Our results reveal first benefits and limitations, but we can also conclude the need of longitudinal and independent investigations for which we herewith lay the foundation

Naming the Pain in Requirements Engineering: A Design for a Global Family of Surveys and First Results from Germany

For many years, we have observed industry struggling in defining a high quality requirements engineering (RE) and researchers trying to understand industrial expectations and problems. Although we are investigating the discipline with a plethora of empirical studies, they still do not allow for empirical generalisations. To lay an empirical and externally valid foundation about the state of the practice in RE, we aim at a series of open and reproducible surveys that allow us to steer future research in a problem-driven manner. We designed a globally distributed family of surveys in joint collaborations with different researchers and completed the first run in Germany. The instrument is based on a theory in the form of a set of hypotheses inferred from our experiences and available studies. We test each hypothesis in our theory and identify further candidates to extend the theory by correlation and Grounded Theory analysis. In this article, we report on the design of the family of surveys, its underlying theory, and the full results obtained from Germany with participants from 58 companies. The results reveal, for example, a tendency to improve RE via internally defined qualitative methods rather than relying on normative approaches like CMMI. We also discovered various RE problems that are statistically significant in practice. For instance, we could corroborate communication flaws or moving targets as problems in practice. Our results are not yet fully representative but already give first insights into current practices and problems in RE, and they allow us to draw lessons learnt for future replications. Our results obtained from this first run in Germany make us confident that the survey design and instrument are well-suited to be replicated and, thereby, to create a generalisable empirical basis of RE in practice

Classification of cosmological milestones

In this paper causal geodesic completeness of FLRW cosmological models is analysed in terms of generalised power expansions of the scale factor in coordinate time. The strength of the found singularities is discussed following the usual definitions due to Tipler and Krolak. It is shown that while classical cosmological models are both timelike and lightlike geodesically incomplete, certain observationally alllowed models which have been proposed recently are lightlike geodesically complete.Comment: RevTeX 4, 12 page

The Geography of Non-formal Manifolds

We show that there exist non-formal compact oriented manifolds of dimension $n$ and with first Betti number $b_1=b\geq 0$ if and only if $n\geq 3$ and $b\geq 2$, or $n\geq (7-2b)$ and $0\leq b\leq 2$. Moreover, we present explicit examples for each one of these cases.Comment: 8 pages, one reference update

The mass and environmental dependence on the secular processes of AGN in terms of morphology, colour, and specific star-formation rate

Galaxy mass and environment play a major role in the evolution of galaxies. In the transition from star-forming to quenched galaxies, Active galactic nuclei (AGN) have also a principal action. However, the connections between these three actors are still uncertain. In this work we investigate the effects of stellar mass and the large-scale environment (LSS), on the fraction of optical nuclear activity in a population of isolated galaxies, where AGN would not be triggered by recent galaxy interactions or mergers. As a continuation of a previous work, we focus on isolated galaxies to study the effect of stellar mass and the LSS in terms of morphology (early- and late-type), colour (red and blue), and specific star formation rate (quenched and star-forming). To explore where AGN activity is affected by the LSS we fix the stellar mass into low- and high-mass galaxies. We use the tidal strength parameter to quantify their effects. We found that AGN is strongly affected by stellar mass in 'active' galaxies (namely late-type, blue, and star-forming), however it has no influence for 'quiescent' galaxies (namely early-type, red, and quenched), at least for masses down to $\rm 10^{10}\,[M_\odot]$. In relation to the LSS, we found an increment on the fraction of SFN with denser LSS in low-mass star forming and red isolated galaxies. Regarding AGN, we find a clear increment of the fraction of AGN with denser environment in quenched and red isolated galaxies, independently of the stellar mass. AGN activity would be 'mass triggered' in 'active' isolated galaxies. This means that AGN is independent of the intrinsic property of the galaxies, but on its stellar mass. On the other hand, AGN would be 'environment triggered' in 'quiescent' isolated galaxies, where the fraction of AGN in terms of sSFR and colour increases from void regions to denser LSS, independently of its stellar mass.Comment: 14 pages, 9 figures (11 pages and 6 figures without appendix), accepted for publication in Astronomy & Astrophysic

Global IT strategic plan for universities in Spain

Many reports show up every year to measure the development and social use of the Information Technologies (IT) in given territorial areas [1, 2]. They exhibit key aspects of reality using a set of indicators. On consolidated reports one can find more qualitative information through the indicator evolution over years. The knowledge society, which Europe drew in Lisbon, leans on a modern higher education system with innovative methods and resources. Universities, that were pioneer in introducing computation and Internet for research, have been walking fast adopting IT also for student instruction, management and government. In Spain, this evolution was sometimes lacked of reflection and evaluation. For this reason, the IT Working Group of the Spanish Association of University Rectors (CRUE in Spanish set of initials) drove in 2004 the confection of an inquest in order to achieve a global assessment of IT in universities [3]. The results showed that the Spanish Universities, in general, adopt a compromised aim with the introduction and use of IT, but frequently it is more reactive than proactive, more improvised than planned. In this paper we explain the work developed inside the IT Working Group of the CRUE, with members from different universities and different knowledge areas that have been working in the next approach of the IT inquest. We resolved to introduce an IT Strategic Plan, shared by all universities in Spain. The aim is to have a flexible but strong tool to guide the IT department on the politic priorities.Peer Reviewe

Why does Latin America Grow More Slowly?

In order to analyze how satisfactory the growth process in Latin America has been over the past 40 years it is important to make relevant comparisons with other experiences. To tackle this issue, the authors focus on the per capita economic growth rate and its contributing factors, comparing the experience of the typical country in Latin America (LAC) with that of benchmark countries, namely a typical country of the rest of the world (ROW) and of its subsets of developed countries (DEV) and East Asian countries (EASIA). They provide some econometric evidence suggesting that the worse institutional quality of Latin America relative to rest of the world, and to a lesser extent, the lower degree of openness and the higher degree of macroeconomic instability, were important factors behind these differences in productivity growth. The rest of the paper includes a description of economic performance of Latin America during the last four decades and a comparison it with the experience of the benchmark countries, accounting exercises in order to examine the contributions of various factors to the differences in performance observed, an econometric model to explore the role of policy and institutional variables as drivers of these contributions, and a conclusion.Economic Development & Growth, Region 1, Latin America