Different transport regimes in a spatially-extended recirculating background

Passive scalar transport in a spatially-extended background of roll convection is considered in the time-periodic regime. The latter arises due to the even oscillatory instability of the cell lateral boundary, here accounted for by sinusoidal oscillations of frequency $\omega$. By varying the latter parameter, the strength of anticorrelated regions of the velocity field can be controled and the conditions under which either an enhancement or a reduction of transport takes place can be created. Such two ubiquitous regimes are triggered by a small-scale(random) velocity field superimposed to the recirculating background. The crucial point is played by the dependence of Lagrangian trajectories on the statistical properties of the small-scale velocity field, e.g. its correlation time or its energy.Comment: 9 pages Latex; 5 figure

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)

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

Country-of-origin effect and millennials’ wine preferences-a comparative experiment

For wine consumers, the country-of-origin effect still exerts significant influence, even though probably differently from what it was earlier, especially for newer consumer seg-ments. Among these, millennials represent the most interesting segment of the present and future, even though studies on millennials’ behaviour are insidious and newer consumer segments are emerging (Generation Z). This study focuses on this parameter through a comparative analysis of French and Italian wines—first, on the country-of-origin effect on millennials’ wine preferences, and second, on the possibility of managing this influence by adopting a wine marketing mix based on the innovative 4Es model. The outcomes of the ex-periment on 121 millennials, despite the limitations of the study, highlight interesting changes—compared with the wine consumption behaviours of the past—regarding the coun-try-of-origin effect and the possibility of managing it. The results confirm, similar to the lit-erature on the 4Es model, the possibility of wide areas of action for wine educational mar-keting initiatives that can change or enhance the country-of-origin perception

Driven classical diffusion with strong correlated disorder

We analyze one-dimensional motion of an overdamped classical particle in the presence of external disorder potential and an arbitrary driving force F. In thermodynamical limit the effective force-dependent mobility mu(F) is self-averaging, although the required system size may be exponentially large for strong disorder. We calculate the mobility mu(F) exactly, generalizing the known results in linear response (weak driving force) and the perturbation theory in powers of the disorder amplitude. For a strong disorder potential with power-law correlations we identify a non-linear regime with a prominent power-law dependence of the logarithm of mu(F) on the driving force.Comment: 4 pages, 2 figures include

Digital transformation and tourist experience co-design: big social data for planning cultural tourism

Digital transformation has completely changed the demand/offering interaction in the travel industry, as well as largely affecting the customer journey. In this direction, “big social data” and user-generated content have become key sources of well-timed and rich knowledge supporting data driven decision approaches addressed the managing of complex relationships. Based on this theoretical framework, the paper suggests how to apply “big social data” in the tourist experience co-design, providing an increased value for the visitors and a better decision making approach for managers. In this respect, the field analysis concentrated specifically on user-generated content regarding the Pompeii Archaeological Site (P.A.S.), to trace valuable insights for the tourist experience. Based on double stage of research – netnographic analysis and a supplementary online survey – the study aimed to detect: (a) tourist perception on the P.A.S.; (b) random chat on the part of internet users (tourists and other browsers, not necessarily visitors) on the topic of the P.A.S.; (c) the main characteristics of the P.A.S. that attract internet user attention; (d) the main topics debated by influencers/opinion leaders managing online discussions on the P.A.S. managerial and theoretical implications were investigated highlighting the main limitations of the study as well

Multi-start heuristics for the Two-Echelon Vehicle Routing Problem

In this paper we address the Two-Echelon Vehicle Routing Problem (2E-VRP), an extension of the classical Capacitated VRP, where the delivery from a single depot to the customers is managed by routing and consolidating the freight through intermediate depots called satellites. We present a family of Multi-Start heuristics based on separating the depot-to-satellite transfer and the satellite-to-customer delivery by iteratively solving the two resulting routing subproblems, while adjusting the satellite workloads that link them. The common scheme on which all the heuristics are based consists in, after having found an initial solution, applying a local search phase, followed by a diversification; if the new obtained solutions are feasible, then local search is applied again, otherwise a feasibility search procedure is applied, and if it successful, the local search is applied on the newfound solution. Different diversification strategies and feasibility search rules are proposed. We present computational results on a wide set of instances up to 50 customers and 5 satellites and compare them with results from the literature, showing how the new methods outperform previous existent methods, both in efficiency and accurac