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Resource capacity and product changeovers must be both considered in the preparation of a realistic production plan. The purpose of this paper is to present a heuristic for enforcing resource availability and the accompanying changeover realities into a continuous‐variable linear programming formulation that would otherwise require a mixed‐integer model. The results from both approaches are compared in terms of objective function values and computational requirements; the effectiveness of the heuristic approach is demonstrated.

A case study search was conducted to identify relevant data sets that could be used to exercise the optimization and heuristic models. The case studies found in the literature were too small and simple compared to the problem complexity desired. The authors developed a case study based on the development of a production plan for a typical flashlight. It includes two end‐products that differ in their bills of materials and process requirements. Basic processes include plastic part preparation and final assembly; various raw materials with pre‐defined lead times are purchased from external suppliers. The results of the LP‐based heuristic and the mixed‐integer programming (MIP) optimization algorithm are then compared through a statistical experiment. The experiment includes four factors: number of products, number of periods, number of machines, and percentage line capacity utilization.

When a MIP algorithm is applied to obtain the results, most of the time the planner would have to wait days or even weeks for the algorithm to provide a solution. However, the authors' linear programming‐based procedure provides the same quality of solution in minutes and for some problems in seconds.

The originality of the heuristic approach resides on the avoidance of the lengthy MIP computer runs. At each iteration, the authors solve the LP production planning problem without changeover considerations, and then subtract from the original capacity the time associated with the changeovers resulting from the last LP solution. After a small number of iterations the heuristic always converges to the optimal MIP solution. The contribution of this research can be appreciated by someone who is using this tool to generate a production plan in a real world factory where setups are important and the results can immediately suggest changes to some of the assumptions or parameters used in the planning exercise.

The efficiency of assembly lines is a critical factor for the competitiveness of industries in the global market. The purpose of this paper is to present a line balancing methodology consisting of the combination of a heuristic model and an exact algorithm with intelligent task location or line zone constraints. The objective is to find a minimum cost solution in a feasible computational time with a realistic cost function considering short‐term operation costs, task‐related and workstation capital investment costs, and workstation paralleling.

The methodology is evaluated using different problem sizes, zone sizes and cycle time scenarios. The quality of results is measured by the closeness to the global optimum and the computational time requirements.

The proposed methodology is found to be highly effective with an average percentage difference of −0.63 percent from the optimum solution. In the experimentation, results are compared against the global optimum in 24 of the 36 scenarios tested. In 23 of the 24 (95.8 percent) results, the largest percentage difference is 0.55 percent. In eight of the 12 cases in which the global optimum is not found, the algorithm with zone constraints provided a better solution than the upper bound available when the simulation model pursuing the optimum is stopped. These unfinished runs are stopped after a minimum run time of 24 hours.

The originality of the methodology is on the strategy used to consider workstation paralleling with task‐related capital investment costs. It is the only one with an exact algorithm considering task‐related capital investment costs in combination with workstation paralleling.

The purpose of this paper is to develop and validate a context-specific scale to assess faculty job satisfaction for Ecuadorian higher education institutions.

A draft questionnaire was developed after reviewing the literature. Then, following a pilot study the questionnaire was administered to a stratified random sample of 261 faculty members of an Ecuadorian University. An exploratory factor analysis based on a pairwise polychoric correlation matrix was carried out to validate the scale.

A 24-item faculty satisfaction questionnaire was developed. The scale showed high reliability and validity. Following an exploratory factor analysis five dimensions emerged: 1) rewards and benefits, 2) IT and facilities services, 3) administrative and other campus services, 4) teaching support and development and 5) working relationships.

Although our sample size is considered good, the ratio subjects to items of 6:1 was just above the recommended minimum. Due to the split questionnaire design for the research support and community services support sections and the fact that more than a half of the participants did not fill them we had to exclude the items from those sections from the analysis.

The scale can be used by higher education institutions to assess faculty satisfaction periodically.

To our knowledge this is the first study to develop a context-specific instrument to measure job satisfaction in Ecuadorian higher education institutions using exploratory factor analysis.

The term “Brazilian popular music” refers to a varied repertoire of musical styles with a strong connection to local culture. The initiatives of representation of this domain of interest occur through adaptations of generic models and strategies coming from contexts and musical styles that differ from the essential characteristics of the national music. The purpose of this paper is to present a characterization of Brazilian popular music as a conceptual model which supports the communication and analysis of this domain and serves as a reference ontology for various applications in the field of Information Science and others.

To achieve the purpose, a mapping about Brazilian popular music was done from a literature review and a data collection with expert users, based on domain analysis theory. From this characterization, the conceptual model was built using an Ontology Engineering approach. To facilitate understanding, the results were described using a more user-friendly notation.

The paper presents a conceptual model as a first semantic reference on Brazilian popular music that serves (1) to better understand, communicate and analyze the domain of Brazilian popular music and, (2) to supply some semantic aspects not covered by the adaptations that have been proposed on the literature for musical representation.

The paper adds a new perspective to the understanding of Brazilian popular music and open opportunity to explore other repertoires about popular music.