A nonmonotone GRASP

A greedy randomized adaptive search procedure (GRASP) is an itera- tive multistart metaheuristic for difficult combinatorial optimization problems. Each GRASP iteration consists of two phases: a construction phase, in which a feasible solution is produced, and a local search phase, in which a local optimum in the neighborhood of the constructed solution is sought. Repeated applications of the con- struction procedure yields different starting solutions for the local search and the best overall solution is kept as the result. The GRASP local search applies iterative improvement until a locally optimal solution is found. During this phase, starting from the current solution an improving neighbor solution is accepted and considered as the new current solution. In this paper, we propose a variant of the GRASP framework that uses a new “nonmonotone” strategy to explore the neighborhood of the current solu- tion. We formally state the convergence of the nonmonotone local search to a locally optimal solution and illustrate the effectiveness of the resulting Nonmonotone GRASP on three classical hard combinatorial optimization problems: the maximum cut prob- lem (MAX-CUT), the weighted maximum satisfiability problem (MAX-SAT), and the quadratic assignment problem (QAP)

An approximation scheme for an Eikonal Equation with discontinuous coefficient

We consider the stationary Hamilton-Jacobi equation where the dynamics can vanish at some points, the cost function is strictly positive and is allowed to be discontinuous. More precisely, we consider special class of discontinuities for which the notion of viscosity solution is well-suited. We propose a semi-Lagrangian scheme for the numerical approximation of the viscosity solution in the sense of Ishii and we study its properties. We also prove an a-priori error estimate for the scheme in an integral norm. The last section contains some applications to control and image processing problems

Approaching deterministic and probabilistic truth: a unified account

The basic problem of a theory of truth approximation is defining when a theory is \u201cclose to the truth\u201d about some relevant domain. Existing accounts of truthlikeness or verisimilitude address this problem, but are usually limited to the problem of approaching a \u201cdeterministic\u201d truth by means of deterministic theories.Ageneral theory of truth approximation, however, should arguably cover also cases where either the relevant theories, or \u201cthe truth\u201d, or both, are \u201cprobabilistic\u201d in nature. As a step forward in this direction, we first present a general characterization of both deterministic and probabilistic truth approximation; then, we introduce a new account of verisimilitude which provides a simple formal framework to deal with such issue in a unified way. The connections of our account with some other proposals in the literature are also briefly discussed

Wine tourism as a non-core business strategy for small wineries

In recent years, wineries have been implementing increasingly more wine tourism activities as complementary or supplementary services to enhance their wine products. This paper adopts an inductive research paradigm based on grounded investigation; more specifically, this paper begins with a case study and expands to involve further similar evidence. The findings of this study show that, for wineries, wine tourism represents a fundamental opportunity for communication (institutional and commercial), distribution (as a form of direct channel), and growth (to include tasting, catering, hospitality, and so on). Most importantly, for both scholars and managers, the results of the research highlight that wine tourism can become the main source of the business value, especially in the case of small wineries (an example of which is examined in the case study under analysis). In these situations, however, wine production still characterizes the business because, otherwise, there can be no wine tourism, but wine production is not realistically critical to the business in terms of survival, competitiveness, and development

A new subfamily of fungal subtilases: structural and functional analysis of a Pleurotus ostreatus member

Pleurotus ostreatus produces several extracellular proteases which are believed to be involved in the regulation of the ligninolytic activities of this fungus. Recently, purification and characterization of the most abundant P. ostreatus extracellular protease (PoSl) have been reported. The sequence of the posl gene and of the corresponding cDNA has been determined, allowing the identification of its pre- and pro-sequences. A mature protein sequence has been verified by mass spectrometry mapping, the N-glycosylation sites have been identified and the glycosidic moieties characterized. Mature PoSl shows a cleaved peptide bond in the C-terminal region, which remains associated with the catalytic domain in a non-covalent complex. Reported results indicate that this enzyme is involved in the activation of other P. ostreatus secreted proteases, thus suggesting its leading role in cascade activation mechanisms. Analyses of the PoSl sequence by homology search resulted in the identification of a DNA sequence encoding a new protease, homologous to PoSl, in the Phanerochaete chrysosporium genome. A new subgroup of subtilisin-like proteases, belonging to the pyrolysin family, has been defined, which includes proteases from ascomycete and basidiomycete fungi

Intellectual capital in nonprofit organizations: a focus on social capital as a marketing enabler

Design/methodology/approach: After a literature review about the intellectual capital (IC) and the social capital (SC) in the non-profit sector (NPS), at either national or international level, the study presents a bibliometric-systematic literature review (B-SLR) of the field in question. Purpose: The research has the aim of exploring whether and how relevant studies about nonprofit organizations (NPOs) have so far investigated the fruitful effects that can be generated by proactive governance, management and marketing of their IC – particularly when considering its extension to SC – with relation to the promotion of corporate reputation. Findings: According to a quantitative (more bibliometric) perspective, the scientific interest on this specific issue has not always been constant and methodical, while three themes (institutional scope, human resources and operational functioning) have so far mostly been analyzed according to a qualitative (and therefore more systematic) perspective. Originality/value: Despite some recent trends aimed at re-evaluating the effect of intangible assets in any organization, there is still some reticence within the NPS to consider the importance of these resources. This orientation also extends to IC, and more specifically to SC, which should now be considered as relevant factors in the creation of value for any socioeconomic organization, both nationally and internationally