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To introduce an algorithm to solve inequalities defined by real functions on a certain compact set D of a general metric space (E, D). The device is based on α‐dense curves.

The solution of inequalities using α‐dense curves and also an approach to a global optimization technique, similarly obtained to that of the inequalities.

A new method is presented. The algorithm for solving inequalities is described which is based on a proven result. Inequalities of n‐variable dependence are reduced by transformation using α‐dense curves.

The research is a continuation of studies that resulted in a new method called Alienor for solving global optimization problems associated with multi‐variable functions.

Based on earlier research by the authors α‐dense curves have been used which allow the transformation of a n‐variables global optimization problem into a one‐variable global one. This paper gives a new method for quickly solving the one‐variable problem.

This paper aims to present a new method for obtaining points of the set determined by the closure of the real projections of the zeros of each partial sum 1+2^s+ċ+n^s, n≥2, s=σ+it, of the Riemann zeta function and to show several applications of this result.

The authors utilize an auxiliary function related to a known result of Avellar that characterizes the set of points of interest. Several figures and numerical experiences are presented to illustrate the various properties which are studied.

It is first shown that each point of the image of the auxiliary function can be approximated by points of the image of the function formed by the approximants. Secondly, conditions are given on the auxiliary function to obtain points satisfying the property of density which is studied. Finally, by using these conditions, several useful applications are presented to the case n=4 and σ₀=0 which a more specific criterion is also given.

This research is applicable for finding accumulation points of the set of the real projection of the zeros of the approximants on its critical interval. An exact interval included in this set is given for the case n=4. Also, it is demonstrated that the point 0 is included for a large set of values of n.

The method employed is original and it contributes to the study on the properties of the density of the real parts of the zeros of a particular class of entire functions.

The purpose of this chapter is to solve multi-objective formulation for traveling salesman and transportation problems. Computations are based on real data for the road freight transportation of a Spanish company. The company was selected because of its importance in Spanish economy and market. This company is important in the whole country; however, it has its higher importance in the northern part of Spain. The requirements for these models are the minimization of total distance and the CO₂ emissions. To achieve this, it is required to know and carry out the minimization of the total distance traveled by the trucks during the deliveries. The deliveries are going to be executed between the different locations, nodes, in the region, and Elorrio, where the depot is situated. The data have been used to decide the best route in order to obtain a minimization of cost for the company. As it was mentioned earlier, the problems are focused on the reduction of the amount of CO₂ emissions and minimization of total distance; by studying different parameters, the best solutions of route transportation have been obtained. The software used to solve these models is CPLEX solver with AMPL programming language.

The purpose of this chapter is to optimize multi-criteria formulation for green vehicle routing problems by mixed integer programming. This research is about the road freight transportation of a Spanish company of groceries. This company has more power in the north of Spain and hence it was founded there. The data used for the computational experiments are focused in the northern region of Spain. The data have been used to decide the best route in order to obtain a minimization of costs for the company. The problem focused on the distance traveled and the altitude difference; by studying these parameters, the best solution of route transportation has been made. The software used to solve this model is CPLEX solver with AMPL programming language. This has been helpful to obtain the results for the research and some conclusions have been obtained from them.

In this chapter, four bi-objective vehicle routing problems are considered. Weighted-sum approach optimization models are formulated with the use of mixed-integer programming. In presented optimization models, maximization of capacity of truck versus minimization of utilization of fuel, carbon emission, and production of noise are taken into account. The problems deal with real data for green logistics for routes crossing the Western Pyrenees in Navarre, Basque Country, and La Rioja, Spain.

Heterogeneous fleet of trucks is considered. Different types of trucks have not only different capacities, but also require different amounts of fuel for operations. Consequently, the amount of carbon emission and noise vary as well. Modern logistic companies planning delivery routes must consider the trade-off between the financial and environmental aspects of transportation. Efficiency of delivery routes is impacted by truck size and the possibility of dividing long delivery routes into smaller ones. The results of computational experiments modeled after real data from a Spanish food distribution company are reported. Computational results based on formulated optimization models show some balance between fleet size, truck types, and utilization of fuel, carbon emission, and production of noise. As a result, the company could consider a mixture of trucks sizes and divided routes for smaller trucks. Analyses of obtained results could help logistics managers lead the initiative in environmental conservation by saving fuel and consequently minimizing pollution. The computational experiments were performed using the AMPL programming language and the CPLEX solver.

The current study aims to investigate the temporal mechanisms in HRM systems by focusing on how HRM systems evolve over time and how such changes affect organizational innovation.

This paper draws on organizational entrainment theory to examine how pace of change in employee involvement programs (EIPs) influences innovation via data from an eight-year longitudinal survey collected by Statistics Canada. The final sample includes 15,679 workplace–year observations.

This research shows that the effects of HRM programs on performance are more than just the mean effect – the pace of change by which changes are implemented in HRM programs matters in the long run. The optimal level of change pace occurs when the EIPs are changing at a pace that entrains (or synchronizes) with organizational rhythm of strategic changes. Results suggest that change pace in EIPs has an inverted-U-shaped relationship with both pace and quality of innovation. The curvilinear effect is more pronounced for organizations with relatively lower mean level of EIPs.

First, this study captures only key measures of the EIPs and may not be generalizable to other dimensions of the HR systems. Second, the results of this paper should be interpreted at the HR program level or bundles of HR practices – the findings may not be generalizable to lower levels of analysis. Third, as a result of annual measurement, this study cannot capture short-lived minor dynamic HR misfits where workplaces quickly adjust to regain alignment. Fourth, to attain meaningful and consistent measures of strategic HR change, this study only includes surviving workplaces with at least five years of observations.

This paper provides insights to managers and business leaders on how to implement strategic changes in HRM systems effectively to attain sustained innovation outcomes in the long run. To achieve an optimal level of innovation, organizations need to consider not only what and how many EIPs should be used but also how to strategically change EIPs to meet dynamic internal and external changes.

The current research introduces organizational entrainment theory to explain and empirically test the conflicting predictions of the universalist and contingency perspectives on the effects of strategic changes in HRM.

The purpose of this paper – based on the conviction that the human resource is by far the most strategic or distinctive resource available to firms competing in hospitality and tourism industries – is to objectively analyze the research on HR developed in the domain of tourism and hospitality management between 1997 and 2016. The aim is to “identify” and “represent” the “intellectual structure” of the field examined.

“Bibliometric” methods are utilized: document citation and co-citation analyses, as well as social network analysis (SNA).

The paper provides an interesting inventory of the theoretical foundations of knowledge developed around HR in the field under study by different theoretical frameworks and scientific disciplines, such as marketing or psychology. However, its main contribution is to identify an important gap in the literature in the specific area of management.

The present study has several limitations resulting from the utilization of “bibliometric” methods applied in the analyses performed. As for the implications, these are more than obvious.

The authors believe that research developed here provides – through a kind of “meta-analysis” – a valuable outlet from which future researchers could benefit, giving them easier access to the theoretical foundations on which HR research in the field in question is based. This work also suggests some paths for future development or research in the field within the context of hospitality and tourism industries.

Previous research suggests that constructions of legitimacy play a central role in the development of markets, yet little attention has been given to how that legitimacy is constructed through the material practices of market actors. This paper aims to address this gap via an examination of cultural intermediaries in the fine wine market of Shanghai.

An interpretive thematic analysis was carried out on data from 13 semi-structured interviews with fine wine intermediaries based primarily in Shanghai (5 wine writers/educators; 5 sommeliers/retailers; 3 brand representatives).

The dimensions of the legitimation of wine were examined, identifying three key themes: the legitimacy of intermediaries as experts; the legitimacy of a particular mode of wine consumption; the legitimacy of the intermediaries as exemplars for not-yet-legitimate consumers. These findings suggest that cultural intermediaries’ personal, consuming preferences and practices are significant to the formation of a new market, and that they must negotiate potential tensions between interactions with legitimate, not-yet-legitimate and illegitimate consumers.

Limitations with regard to generalizability are discussed with regard to potential future research.

The focus on cultural intermediaries and dimensions of legitimation can be used to examine the case of other emerging markets to anticipate the pathways to institutionalizing new forms of taste and consumption practices.

The paper offers an empirical insight into the market dynamics of distinction in the Shanghai wine market and conceptual insight into the importance of cultural intermediaries as exemplar consumers.

This study aims to analyze the relationships between knowledge management, internationalization and ambidexterity, also exploring the influence of these variables on Spanish hotel chain performance. Hypotheses are proposed from the dynamic capabilities and knowledge-management views of the firm.

The research model was tested on a sample of 70 Spanish hotel chains applying variance-based structural equation modeling (partial least squares).

The results show that Spanish hotel chains that use knowledge management processes achieve a greater degree of internationalization and this increases their organizational ambidexterity. This study can also confirm a direct, positive and significant relationship between organizational ambidexterity and performance.

This research shows that knowledge may be considered an essential resource to improve hotel firms’ results. Spanish hotel firms should manage their knowledge to stimulate international activity because this could enhance learning capabilities related to organizational ambidexterity and positively influence performance.

The present paper analyzes relationships between variables that had not previously been analyzed in a single model, including knowledge management, the degree of internationalization of hotel chains, ambidexterity and performance.