Sufficient conditions for a digraph to admit a (1,=l)-identifying code

A (1, = `)-identifying code in a digraph D is a subset C of vertices of D such that all distinct subsets of vertices of cardinality at most ` have distinct closed in-neighbourhoods within C. In this paper, we give some sufficient conditions for a digraph of minimum in-degree d - = 1 to admit a (1, = `)- identifying code for ` ¿ {d -, d- + 1}. As a corollary, we obtain the result by Laihonen that states that a graph of minimum degree d = 2 and girth at least 7 admits a (1, = d)-identifying code. Moreover, we prove that every 1-in-regular digraph has a (1, = 2)-identifying code if and only if the girth of the digraph is at least 5. We also characterize all the 2-in-regular digraphs admitting a (1, = `)-identifying code for ` ¿ {2, 3}.Peer ReviewedPostprint (author's final draft

New directions in water resources management: The role of water pricing policies

Water resources will face increasing competition and higher environmental concerns during this century. To meet these challenges, the new Water Framework Directive has drawn up an integrated framework and established the basic principles for a sustainable water policy in the European Union. The introduction of water prices reflecting the true cost of irrigation is one of its most innovative components. In this paper, a positive mathematical programming model is developed to assess the environmental and socio-economic impacts of water pricing policies in Spanish irrigated lands. The model interface allows friendly use and easy replication in a large number of irrigation districts, selected throughout the Spanish territory. The model results show the impact on environmental indicators, water consumption, cropping patterns, technology adoption, labor, farmers' income, and the water agency revenues when different scenarios of cost recovery are considered. It is argued that this modeling approach may be used as a management tool to assist in the implementation of the cost recovery approach of the new Water Framework Directive

Identifying codes from the spectrum of a graph or digraph

Peer ReviewedPostprint (author's final draft

Negotiating with a logical-linguistic protocol in a dialogical framework

This book is the result of years of reflection. Some time ago, while working in commodities, the author felt how difficult it was to decide the order in which to use arguments during a negotiation process. What would happen if we translated the arguments into cards and played them according to the rules of the Bridge game? The results were impressive. There was potential for improvement in the negotiation process. The investigation went deeper, exploring players, cards, deals and the information concealed in the players´ announcements, in the cards and in the deals. This new angle brought the research to NeuroLinguistic Patterns and cryptic languages, such as Russian Cards. In the following pages, the author shares her discovery of a new application for Logical Dialogues: Negotiations, tackled from basic linguistic structures placed under a dialogue form as a cognitive system which ‘understands’ natural language, with the aim to solve conflicts and even to serve peace

A family of mixed graphs with large order and diameter 2

A mixed regular graph is a connected simple graph in which each vertex has both a fixed outdegree (the same indegree) and a fixed undirected degree. A mixed regular graphs is said to be optimal if there is not a mixed regular graph with the same parameters and bigger order. We present a construction that provides mixed graphs of undirected degree qq, directed degree View the MathML sourceq-12 and order 2q22q2, for qq being an odd prime power. Since the Moore bound for a mixed graph with these parameters is equal to View the MathML source9q2-4q+34 the defect of these mixed graphs is View the MathML source(q-22)2-14. In particular we obtain a known mixed Moore graph of order 1818, undirected degree 33 and directed degree 11 called Bosák’s graph and a new mixed graph of order 5050, undirected degree 55 and directed degree 22, which is proved to be optimal.Peer ReviewedPostprint (author's final draft

Have Spanish companies built greater entrepreneurship after privatization?

This study analyses some of the strategic and organizational changes experienced in public firms following privatization in its double facet: sale of companies and deregulation. Specifically, we analyse the process of innovation in terms of products, processes and organization. We also look into the development of new businesses and strategic renewal, which in the end shape the entrepreneurial capacity of a company. A sample of Spanish firms which were privatized between 1985 and 2000 shows that after privatization, these companies have experienced a significant increase in entrepreneurship. These changes are even more appreciable when a high sector competition is added to the ownership shift. Once they join the private sector, their level of product, process and organizational innovation is higher. They also develop new businesses at national level, reinforce their international activity and embark on strategic renewal processes by shedding the lesser profitable businesses and modifying their competitive strategy so as to gain efficiency

The comovement between height and some economic development indicators in Spain

This paper investigates the relationship between height and some measures of human welfare in Spain for the period 1850-1978. For that purpose, we employ several filtering methods to measure the correlation between variables such as first order differences, deterministic trends, the Hodrick and Prescott filter, the band-pass filter or den Haan (2000)’s methodology which uses a new set of statistics to characterize the co-movement between variables to capture the dynamic between variables. We always find a strong and positive correlation between height and GDP per cápita, height and the weight of health services in total consumption, and height and openness. By contrast, we have a negative correlation between height and the mortality rate and height and the ratio between the deflator of private consumption and the GDP deflator. By applying den Haan (2000)’s method, we find that the comovement between height and GDP per cápita is always positive, increasing in the medium and long-run. This correlation is higher after the Spanish Civil War (1936-1939). We also observe that height and mortality rate have a negative correlation in the medium-run. Other health indicators such as the weight of health services in total consumption and the ratio between the deflator of private consumption and the GDP deflator show a positive and negative co-movement in the short-run, respectively. Nevertheless, they change their sign of correlation in the long-run. Finally, we observe a positive co-movement between height and illiteracy rate in the short-run, a negative one in the long-run, and a strong and positive comovement between height and the grade of openness.Height, physical stature, anthropometrics, education, economic development, VAR forecast errors

A Quality Model for Actionable Analytics in Rapid Software Development

Background: Accessing relevant data on the product, process, and usage perspectives of software as well as integrating and analyzing such data is crucial for getting reliable and timely actionable insights aimed at continuously managing software quality in Rapid Software Development (RSD). In this context, several software analytics tools have been developed in recent years. However, there is a lack of explainable software analytics that software practitioners trust. Aims: We aimed at creating a quality model (called Q-Rapids quality model) for actionable analytics in RSD, implementing it, and evaluating its understandability and relevance. Method: We performed workshops at four companies in order to determine relevant metrics as well as product and process factors. We also elicited how these metrics and factors are used and interpreted by practitioners when making decisions in RSD. We specified the Q-Rapids quality model by comparing and integrating the results of the four workshops. Then we implemented the Q-Rapids tool to support the usage of the Q-Rapids quality model as well as the gathering, integration, and analysis of the required data. Afterwards we installed the Q-Rapids tool in the four companies and performed semi-structured interviews with eight product owners to evaluate the understandability and relevance of the Q-Rapids quality model. Results: The participants of the evaluation perceived the metrics as well as the product and process factors of the Q-Rapids quality model as understandable. Also, they considered the Q-Rapids quality model relevant for identifying product and process deficiencies (e.g., blocking code situations). Conclusions: By means of heterogeneous data sources, the Q-Rapids quality model enables detecting problems that take more time to find manually and adds transparency among the perspectives of system, process, and usage.Comment: This is an Author's Accepted Manuscript of a paper to be published by IEEE in the 44th Euromicro Conference on Software Engineering and Advanced Applications (SEAA) 2018. The final authenticated version will be available onlin

Nonlinear model predictive control for hydrogen production in an ethanol steam reformer with membrane separation

© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksThis paper presents a new Nonlinear Model Predictive Control (NMPC) design for an Ethanol Steam Reformer with Pd-Ag membrane separation stage. The reformer is used to produce pure hydrogen able to feed a Proton Exchange Membrane Fuel Cell. Mass and energy balances are used to obtain the nonlinear dynamic model of both the reforming and the separation stages. Constraints, system nonlinearities and flexible cost function are the main reasons to select an NMPC controller, which is tested against the ordinary differential equations as simulation model, and has an internal model based on the sample data technique.Accepted versio

Chloroplast damage induced by the inhibition of fatty acid synthesis triggers autophagy in chlamydomonas

Fatty acids are synthesized in the stroma of plant and algal chloroplasts by the fatty acid synthase complex. Newly synthesized fatty acids are then used to generate plastidial lipids that are essential for chloroplast structure and function. Here, we show that inhibition of fatty acid synthesis in the model alga Chlamydomonas reinhardtii activates autophagy, a highly conserved catabolic process by which cells degrade intracellular material under adverse conditions to maintain cell homeostasis. Treatment of Chlamydomonas cells with cerulenin, a specific fatty acid synthase inhibitor, stimulated lipidation of the autophagosome protein ATG8 and enhanced autophagic flux. We found that inhibition of fatty acid synthesis decreased monogalactosyldiacylglycerol abundance, increased lutein content, down-regulated photosynthesis, and increased the production of reactive oxygen species. Electron microscopy revealed a high degree of thylakoid membrane stacking in cerulenin-treated cells. Moreover, global transcriptomic analysis of these cells showed an up-regulation of genes encoding chloroplast proteins involved in protein folding and oxidative stress and the induction of major catabolic processes, including autophagy and proteasome pathways. Thus, our results uncovered a link between lipid metabolism, chloroplast integrity, and autophagy through a mechanism that involves the activation of a chloroplast quality control system.Ministerio de Economía y Competitividad BFU2015-68216-PJunta de Andalucía CVI-7336, BIO2015-74432-JI