Search results for "OPTIMIZATION"
showing 10 items of 2824 documents
The Role of Individual-Media Relationship and Consumer Personal Factors on Spanish Teenagers' Mobile Social Networking Sites Usage
2014
Social Networking Sites (SNS) are gaining momentum as powerful tools of marketing communications. Mobile phones are becoming one of the most popular devices for accessing Social Networking Sites. In Spain, 44% of Social Networking Sites users access these sites on a daily basis while 79% of them access these sites on a weekly basis. Furthermore, it is notable that over 70% of Social Networking Sites users talk about and recommend commercial brands. This justifies the interest of the study of Social Networking Sites users from a marketing perspective. The aim of this research is to assess the influence of consumers` personal factors (attitude, innovativeness and gender) and individual-media …
CEO tenure and ownership mode choice of Chinese firms: The moderating roles of managerial discretion
2014
Abstract Based on upper echelon theory, this study has explored how CEO tenure affects ownership mode choice of Chinese firms investing abroad, and how some organizational factors, such as firm size, firm age and CEO duality, moderate this relationship. Using secondary data, this study finds CEO tenure has a positive relationship with the choice of full control mode, CEO duality can reinforce this relationship, but firm size and firm age have no significant moderating effect.
Comparative evaluation of some interactive reference point-based methods for multi-objective optimisation
1999
Many real-world optimisation applications include several conflicting objectives of possibly nondifferentiable character. However, the lack of computationally efficient, interactive methods for nondifferentiable multi-objective optimisation problems is apparent. To satisfy this demand, a method called NIMBUS has been developed. Two versions of the basic method are presented and compared both theoretically and computationally. In order to give variety to the comparison, a related approach, called reference direction method is included. Theoretically, the methods differ in handling the information requested from the user. Numerical experiments indicate differences in computational efficiency …
Business performance and social media: Love or hate?
2014
Abstract The social media space has become a common place for communication, networking, and content sharing. Many companies seek marketing and business opportunities via these platforms. However, the link between resources generated from these sites and business performance remains largely unexploited. Both managers and financial advisors can profit from the lessons learned in this study. We conceptualize four channels by which social media impacts financial, operational, and corporate social performance: social capital, customers’ revealed preferences, social marketing, and social corporate networking. An empirical test of our framework shows that ‘followers’ and ‘likes’ positively influe…
Scatter tabu search for multiobjective clustering problems
2011
We propose a hybrid heuristic procedure based on scatter search and tabu search for the problem of clustering objects to optimize multiple criteria. Our goal is to search for good approximations of the efficient frontier for this class of problems and provide a means for improving decision making in multiple application areas. Our procedure can be viewed as an extension of SSPMO (a scatter search application to nonlinear multiobjective optimization) to which we add new elements and strategies specially suited for combinatorial optimization problems. Clustering problems have been the subject of numerous studies; however, most of the work has focused on single-objective problems. Clustering u…
Tabu search with strategic oscillation for the maximally diverse grouping problem
2013
We propose new heuristic procedures for the maximally diverse grouping problem (MDGP). This NP-hard problem consists of forming maximally diverse groups—of equal or different size—from a given set of elements. The most general formulation, which we address, allows for the size of each group to fall within specified limits. The MDGP has applications in academics, such as creating diverse teams of students, or in training settings where it may be desired to create groups that are as diverse as possible. Search mechanisms, based on the tabu search methodology, are developed for the MDGP, including a strategic oscillation that enables search paths to cross a feasibility boundary. We evaluate co…
On the generalized directed rural postman problem
2014
The generalized directed rural postman problem (GDRPP) is a generic type of arc routing problem. In the present paper, it is described how many types of practically relevant single-vehicle routing problems can be modelled as GDRPPs. This demonstrates the versatility of the GDRPP and its importance as a unified model for postman problems. In addition, an exact and a heuristic solution method are presented. Computational experiments using two large sets of benchmark instances are performed. The results show high solution quality and thus demonstrate the practical usefulness of the approach.
GRASP with path relinking for the orienteering problem
2014
In this paper, we address an optimization problem resulting from the combination of the well-known travelling salesman and knapsack problems. In particular, we target the orienteering problem, originated in the context of sport, which consists of maximizing the total score associated with the vertices visited in a path within the available time. The problem, also known as the selective travelling salesman problem, is NP-hard and can be formulated as an integer linear program. Since the 1980s, several solution methods for this problem have been developed and applied to a variety of fields, particularly in routing and tourism. We propose a heuristic method—based on the Greedy Randomized Adapt…
Improving demand forecasting accuracy using nonlinear programming software
2006
We address the problem of forecasting real time series with a proportion of zero values and a great variability among the nonzero values. In order to calculate forecasts for a time series, the model coefficients must be estimated. The appropriate choice of values for the smoothing parameters in exponential smoothing methods relies on the minimization of the fitting errors of historical data. We adapt the generalized Holt–Winters formulation so that it can consider the starting values of the local components of level, trend and seasonality as decision variables of the nonlinear programming problem associated with this forecasting procedure. A spreadsheet model is used to solve the problems o…
Constructing Good Solutions for the Spanish School Timetabling Problem
1996
In the school timetabling problem a set of lessons (combinations of classes, teachers, subjects and rooms) has to be scheduled within the school week. Considering classes, teachers and rooms as resources for the lessons, the problem may be viewed as the scheduling of a project subject to resource constraints. We have developed an algorithm with three phases. In Phase I an initial solution is built by using the scheme of parallel heuristic algorithm with priority rules, but imbedding at each period the construction of a maximum cardinality independent set on a resource graph. In Phase II a tabu search procedure starts from the solution of Phase I and obtains a feasible solution to the proble…