Abstract
We propose two exact algorithms for two-dimensional orthogonal packing problems whose main components are simple mixed-integer linear programming models. Based on the different forms of time representation in scheduling formulations, we extend the concept of multiple time grids into a second dimension and propose a hybrid discrete/continuous-space formulation. By relying on events to continuously locate the rectangles along the strip height, we aim to reduce the size of the resulting mathematical problem when compared to a pure discrete-space model, with hopes of achieving a better computational performance. Through the solution of a set of 29 test instances from the literature, we show that this was mostly accomplished, primarily because the associated search strategy can quickly find good feasible solutions prior to the optimum, which may be very important in real industrial environments. We also provide a comprehensive comparison to seven other conceptually different approaches that have solved the same strip packing problems.

Abstract
Markets today are characterized by enormous uncertainty in demand that combined with the increasing complexity of new products and competition, has forced companies to adopt new collaboration strategies with its business partners. SMEs need to form non-hierarchical networks where they can complement their capabilities and resources, achieve higher added value and higher control of the business. In these environments, decision making becomes decentralized and operations' planning presents new challenges and becomes more collaborative. An integrated solution for non-hierarchical networks collaborative planning is presented in this paper. The solution proposed includes two collaborative planning scenarios (aggregate and detailed), applied in different phases of non-hierarchical networks' lifecycle, which allows SME's to negotiate prices and delivery times in a collaboratively way. The solution considers requirements from companies belonging to three different industrial sectors, assuring its wide applicability. © 2011 Research Institute for Ope.

Abstract
The last decade has been characterized by times of change, including increasing levels of globalization and competition. Collaboration allowed SMEs to respond effectively to the development of new complex products and services but presented new barriers concerning the management of their business processes and relations with partners. This paper presents a new collaborative aggregate planning for non-hierarchical business networks, where SMEs collaborate in the selection of partners and definition of the operations plan required to specify, manufacture and distribute a custom made products. The proposed approach is based on negotiations undertaken by the partners in order to promote the creation of alternative operations plans and allow a multicriteria evaluation of the involved costs and delivery dates. The proposed approach promotes the reduction of communication between partners, a reactive analysis of changes to planning and associated impact, enhancement of trust (since all partners have the same weight on the decision process).

Abstract

Abstract
This paper describes and discusses the results of an empirical study about social-networks/microblogging adoption in a financial institution. Social networking at the workplace literature is overviewed and then presented the methodology and hypothesis of the study. Interviews, a survey and a experimental pilot were used as data collection methods. An extract of the results related with the experimental pilot are discussed and some conclusions derived from them.

Abstract
Performance management in collaborative networks of organisations is a complex process due to the multiplicity of competing perspectives upon it. One of the more sensitive phases of this process is the agreement of the actors in the network regarding the performance evaluation model whose design is considered of great importance in the research literature. This paper proposes a method for the design of performance evaluation systems in collaborative networks through an innovative combination of performance information classification and multi-criteria decision model. The method is implemented in a web-based collaborative platform that enables the members of a collaborative network to efficiently achieve specific performance models that result from a collective and negotiated construction.