An Exploratory Study of Field Failures

Field failures, that is, failures caused by faults that escape the testing phase leading to failures in the field, are unavoidable. Improving verification and validation activities before deployment can identify and timely remove many but not all faults, and users may still experience a number of annoying problems while using their software systems. This paper investigates the nature of field failures, to understand to what extent further improving in-house verification and validation activities can reduce the number of failures in the field, and frames the need of new approaches that operate in the field. We report the results of the analysis of the bug reports of five applications belonging to three different ecosystems, propose a taxonomy of field failures, and discuss the reasons why failures belonging to the identified classes cannot be detected at design time but shall be addressed at runtime. We observe that many faults (70%) are intrinsically hard to detect at design-time

Guidelines for emergy evaluation of first, second and third generation biofuels

Due to growing interest in biofuels as alternative renewable energy sources, several recent studies have assessed the sustainability of their production. Emergy is a widely used environmental indicator for this purpose, as it counts exploitation of natural resources and direct and indirect solar energy requirements of biofuel production. Depending on whether a biofuel is first, second or third generation, its production system differs in nature and the indications derived from emergy evaluations vary as well. This article aims to provide guidelines on how to interpret and properly use the results of emergy evaluation of first, second and third generation biofuels. These guidelines are useful for correct emergy assessment of biofuels and clarify the actual meaning of emergy evaluation outcomes

Sustainability Assessment of Biorefinery Systems Based on Two Food Residues in Africa

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Sustainability assessment of selected biowastes as feedstocks for biofuel and biomaterial production by emergy evaluation in five African countries

11siAfrica is a continent with enormous natural resources in the form of biomass and innovative ways are needed to exploit those ones available from agricultural processes and other production systems. This paper aims to assess the sustainability of a set of potential feedstocks for the production of biofuels and other value added products in Egypt, Ghana, Kenya, Morocco and South Africa. These feedstocks are residues from agricultural and industrial food processing systems that we assess by emergy evaluation for insights into their sustainability. The feedstocks are grouped into sugar-rich (corn stover, cassava peels, pineapple peels, olive oil pomace and rejected bananas) and nutrient-rich (cocoa pods, discarded cabbage leaves, cattle manure and soybean processing residues). Where possible, comparison is made between traditional and commercial production of the same good. Despite higher environmental impacts, commercial systems were found to perform better in exploiting natural resources. Finally, sugar-and nutrient-rich feedstocks were compared on the basis of glucan and ash content, respectively. Cassava peels and cattle manure gave the best performance from an emergy point of view. This approach enabled emergy evaluation of feedstocks that also considered their potential for the production of useful bioproductsreservedmixedSaladini, Fabrizio; Vuai, Said A.; Langat, Benard K.; Gustavsson, Mathias; Bayitse, Richard; Gidamis, Andrew B.; Belmakki, Mohammed; Owis, Amal S.; Rashamuse, Konanani; Sila, Daniel N.; Bastianoni, SimoneSaladini, Fabrizio; Vuai, Said A.; Langat, Benard K.; Gustavsson, Mathias; Bayitse, Richard; Gidamis, Andrew B.; Belmakki, Mohammed; Owis, Amal S.; Rashamuse, Konanani; Sila, Daniel N.; Bastianoni, Simon

Univariate and multivariate Cox models on time to change of first AED for lack of Efficacy.

<p>Univariate and multivariate Cox models on time to change of first AED for lack of Efficacy.</p

Clinical characteristics and oncological therapies.

<p>Clinical characteristics and oncological therapies.</p

Univariate and multivariate Cox models on time to change of first AED for adverse Effects.

<p>Univariate and multivariate Cox models on time to change of first AED for adverse Effects.</p

Antiepileptic drugs by timing of administration.

<p>Antiepileptic drugs by timing of administration.</p