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Product lines have emerged in the software industry as an attractive approach to perform planned reuse of code. Nevertheless, a product line solution is not appropriate in all cases and also requires some conditions to be implemented successfully. The literature offers several contributions regarding the adoption of product lines. However, only a few of them are able to support decision-makers in making informed decisions in favor of or against following this approach. We proposed APPLIES, a framework for evaluating the organization's motivation and preparation for adopting product lines. This article presents the second version of the APPLIES framework as well as the second iteration of the evaluation of this approach. This evaluation consisted of (i) a workshop with a practitioner who had experience in adopting the product line production approach and; (ii) a review of the content by five product line experts. The results obtained from the evaluation resulted in modifications to the framework content, mainly to simplify the statements and eliminate redundant elements. Also, we detected new functionalities and modifications that we expect to be resolved in the following evaluation iterations. Further evaluations and improvements are needed to mature the framework. Moreover, we expect to incorporate APPLIES into a process that covers the aspects that a company must consider before deciding to adopt this production paradigm.

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Software product line engineering is a promising paradigm for developing software intensive systems. Among their proven benefits are reduced time to market, better asset reuse and improved software quality. To achieve this, the collection of products of the product line are specified by means of product line models. Feature Models (FMs) are a common notation to represent product lines that express the set of feature combinations that software products can have. Experience shows that these models can have defects. Defects in FMs be inherited to the products configured from these models. Consequently, defects must be early identified and corrected. Several works reported in scientific literature, deal with identification of defects in FMs. However, only few of these proposals are able to explain how to fix defects, and only some corrections are suggested. This paper proposes a new method to detect all possible corrections from a defective product line model. The originality of the contribution is that corrections can be found when the method systematically eliminates dependencies from the FMs. The proposed method was applied on 78 distinct FMs with sizes up to 120 dependencies. Evaluation indicates that the method proposed in this paper scale up, is accurate, and sometimes useful in real scenarios.

The synthesis of the Y 0.5 Sm 0.5 Ba 2 Cu 3 O 7−δ superconducting material by the standard solid state reaction is reported. DC resistivity measurements reveal the improvement of the critical temperature (T c ) when substitution of exact 50-50 mix of Yttrium and Samarium is performed. A bulk T c = 101 K was determined by the criterion of the maximum in the temperature derivative of electrical resistivity. Structure characterization by means the x-ray diffraction technique shows the crystalline appropriated distribution of Yttrium and Samarium to create substantial planar weight disparity (PWD) in alternating layers. This PWD increases T c in copper-oxide superconductors. In order to examine the effect of PWD on the pairing mechanism close to T c , conductivity fluctuation analysis was performed by the method of logarithmic temperature derivative of the conductivity excess. We found the occurrence of Gaussian and genuinely critical fluctuations. Our results are in agreement with reports on YBa 2 Cu 3 O 7-δ , but an enhancement of the Gaussian fluctuation regimes was experimentally detected as a result of the PWD. The correlations of the critical exponents with the dimensionality of the fluctuation system for each Gaussian regime were performed by using the Aslamazov-Larkin theory. The genuinely critical exponent is interpreted by the 3D-XY model as corresponding with the dynamical universality class of the E-model.

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