Towards correct-by-construction product variants of a software product line: GFML, a formal language for feature modules

Software Product Line Engineering (SPLE) is a software engineering paradigm that focuses on reuse and variability. Although feature-oriented programming (FOP) can implement software product line efficiently, we still need a method to generate and prove correctness of all product variants more efficiently and automatically. In this context, we propose to manipulate feature modules which contain three kinds of artifacts: specification, code and correctness proof. We depict a methodology and a platform that help the user to automatically produce correct-by-construction product variants from the related feature modules. As a first step of this project, we begin by proposing a language, GFML, allowing the developer to write such feature modules. This language is designed so that the artifacts can be easily reused and composed. GFML files contain the different artifacts mentioned above.The idea is to compile them into FoCaLiZe, a language for specification, implementation and formal proof with some object-oriented flavor. In this paper, we define and illustrate this language. We also introduce a way to compose the feature modules on some examples.Comment: In Proceedings FMSPLE 2015, arXiv:1504.0301

Endogenous Fiscal Policies, Environmental Quality, and Status-Seeking Behavior.

This paper analyzes endogenous fiscal policy and public decision in an endogenous growth model where agents care about social status and environmental quality. The quest for a higher status is assimilated to a preference for capital wealth. The government uses income tax to finance infrastructure and environmental protection, and maximizes individual welfare. We find that accounting for preferences for social status and environmental quality may lead to an allocation of tax revenue in favor of cleanup effort to the detriment of infrastructure. It does not necessary have a negative impact on growth. Status seeking can however harm economic growth and environmental quality when its motive is important enough. Finally, we show that economic growth is consistent with environmental preservation but is not necessarily welfare-improving as in the case of absence of status-seeking behavior.Endogenous policy; endogenous growth; environmental quality; status-seeking; public expenditure; Wagner's law.

THE MILITARY ART OF THE COMMUNIST PARTY OF VIETNAM IN THE RESISTANCE WAR AGAINST THE US IMPERIALISTS FOR NATIONAL SALVATION (1954 - 1975)

The Communist Party of Vietnam’s military art in the resistance war against the U.S imperialists for national salvation is the continuation of Vietnam’s tradition of fighting the US to save the country. Over thousands of years of fighting to protect the Fatherland and liberate the nation, Vietnam has built an advanced and unique military art and ideology. Vietnam is a small country, often having to fight against an aggressive move with larger and stronger manpower. Therefore, how should Vietnam’s military art and thought develop in order to win the victory? A small country defeating a large country is a bitter contradiction and must face many difficulties and hardships. Solving this contradiction is a great creation, which requires very high intelligence and the art of excellence in war leadership. That is the uniqueness, the development, the characteristic of Vietnamese military thought and art.  Article visualizations

Agri-Food Value Chain Performance during the COVID-19 Pandemic: An Empirical Study of Chu-mango Business Linkages in Dong Thap, Vietnam

This study aims to identify important factors that directly influence value chain performance (quality, responsiveness, flexibility and efficiency), which are explained by value chain integration (collaboration, commitment, coordination and joint decision-making) in the case of unexpected risk (the COVID-19 pandemic). This study contributes to maintaining the business linkage model among farmers – cooperatives – enterprises in the caseof the COVID-19 pandemic and quickly recovering after the COVID-19 pandemic. Structural equation modelling (SEM) was used for data analysis following an iterative process based on theoretical and empirical analyses toobtain a structural model fit and test the research hypothesis. The findings indicate that the VCI positively influenced the VCP of Chu-mango business linkages at the 1% significance level through coordination (Beta = 0.345;construct reliability (CR) = 3.272), collaboration (Beta = 0.289; CR = 3.128), and joint decision-making (Beta = 0.324; CR = 3.245). This study provides empirical data on the relationship between VCI and VCP through the Chu -mango value chain in Dong Thap Province during the COVID-19 pandemic to raise awareness from stakeholders and encourage value chain thinking to improve performance. This result may pave the way for relevant policymakers to look for policies and strategies for better inclusiveness of stakeholders to show the importance of the VCI in improving the performance. Moreover, the study is an empirical case contributing to the agribusiness value chain in a developing country; it applies the agribusiness value chain of the tropical fruit domain and can be used for otheragricultural products in other cases of unexpected risks

L’hypothèse d’utilité relative dans l’analyse économique : enjeux et conséquences.

La fonction d'utilité de l’ homo oeconomicus est synonyme d'absence d'interactions sociales entre agents économiques et d'indépendance des préférences individuelles. Ce postulat d'utilité, dite absolue, est l'objet de nombreuses vérifications empiriques basées à la fois sur des données expérimentales et des données d'enquêtes réelles. Dans le cadre d'une revue de la littérature, cet article présentera, dans un premier temps, des justifications empiriques du postulat d'utilité relative. D'après celui-ci, l'individu aurait tendance à comparer son niveau de vie à une référence de sorte que son bien-être dépendrait en partie de sa position relative dans la société. Cette position relative serait alors assimilée à un statut social dont les enjeux et les conséquences font l'objet de nombreux travaux en analyse économique. Ainsi, dans un deuxième temps, seront présentés les effets de la quête d'un meilleur statut social sur la propriété normative de l'équilibre décentralisé, sur la fiscalité correctrice et la fiscalité redistributive optimale. Cet article met également l'accent sur le rôle de la préférence pour un statut comme un facteur d'explication de la croissance économique ainsi que d'autres phénomènes liés à cette variable tels que l'inégalité, l'évolution du bien-être, la stratification sociale, et la taxation permettant d'atteindre la croissance optimale.Bien-être; Croissance économique; Politique publique; Statut social; Utilité relative.

Utilité relative, politique publique optimale et croissance économique.

Cet article étudie l'impact de la recherche du statut social sur la croissance et la détermination des politiques publiques optimales dans un modèle de croissance avec le secteur public. Le gouvernement prélève des taxes sur le revenus individuel pour financer le bien public, étant un facteur de production. Les individus ont des préférences portant à la fois sur leur consommation et leur statut social. Celui-ci est déterminé par la position relative de l'individu dans la société en termes de richesse. On montre que la quête du statut social a un effet positif sur la croissance dans le cadre d'une économie décentralisée ainsi que sur la croissance optimale définie par le planificateur central. Le modèle démontre aussi que l'existence et la valeur de taux de taxation optimale dépendent étroitement du degré d'interaction sociale et de l'importance que l'individu accorde au statut social dans son utilité.Croissance endogène ; Politique publique optimale ; Utilité relative ; Statut social