Abstract
This paper applies network analysis to study the evolution of aviation networks. It takes a different approach from previous research that usually only explores airline networks. The aviation network of the airports of Lisbon, Faro and Porto, is modelled using the supply of seats and the passenger demand between 2001 and 2010. This analysis is complemented with a study of the commercial evolution of the three airports. It is noticeable the impact of low-cost carriers in the evolution of the configuration of the network over time. A de-concentration effect is also shown to occur, due to the interaction between airport and airline decisions that favour network development. The results of the analysis highlight how critical it has become for airport managers to assess and satisfy the real requirements of the different types of airlines, in order to reduce uncertainty and increase traffic.

Abstract
In this paper, we propose a multiobjective local search metaheuristic for a mean-risk multistage capacity investment problem with process flexibility, irreversibility, lumpiness and economies of scale in capacity costs. In each period, discrete decisions concerning the investment in capacity expansion, and continuous decisions concerning the utilization of the available capacity to satisfy demand are considered. We solve the capacity utilization problems with linear programming, in order to find the minimum capacity for each resource with the other resources remaining unchanged, this way providing information on the feasibility of the discrete investment decisions. Conditional value-at-risk is considered as a risk measure. Results of a computational study are presented, that show the approach is capable of obtaining high-quality approximations to the efficient sets, with a modest computational effort.

Abstract
Regular and non-regular production can often be found in multipurpose batch plants, requiring two distinct operating strategies: campaign and short-term production. This paper describes a sequential approach for the simultaneous scheduling of campaign and short-term products in multipurpose batch plants. Campaign products follow a periodic scheduling and are constrained to a monthly demand and a safety stock level. Shortterm products have a non-periodic scheduling and must respect tight delivery time windows. Our integrated model is based on the Resource-Task Network (RTN) representation proposed by Pantelides (1994) and uses a discrete-time formulation.

Abstract
Virtual Enterprise is one form of collaborative networks that allows partners to exploit emerging business opportunities in a flexible way. Moreover, in the competitive landscape of the twenty-first century, the business model innovation has become increasingly a key element for companies' positioning in the market. Consequently, this paper aims at proposing a set of business model elements to be used by a virtual enterprise in order to explore a new business opportunity for its network. Literature review is used to identify the business model elements and evidence from a pilot case study confirms that these elements are considered in practice.

Abstract
The reality in today's business is to compete with dynamic and shorter market opportunities. In order to cope up with such environment, manufacturing firms, especially small and medium size enterprises (SMEs) are needed to collaborate with each other for mutual benefits. This collaboration offers process enhancement within the environment of virtual enterprise (VE) and contributes towards sharing costly resources and valuable knowledge among manufacturing companies. This research is basically focused on the process collaboration among companies that motivates them achieving identified business opportunities. A collaboration framework is proposed in this paper with respect to VE process mapping. Visualization of such processes is also highlighted though 'Dashboard' user interfaces in order to monitor and control a successful VE.

Abstract
Design and production of small series for specific customer target groups in collaborative networks can help companies to increase their competitiveness. This paper aims to describe a new framework of services for collaborative networking for on-demand productions. After describing the business processes that need to be supported by innovative tools for partner search and collaborative production planning, we describe the developed services and how they are integrated to ease the communication between different activities. © 2012 International Federation for Information Processing.