This paper considers a one-machine scheduling problem where the objective is to minimize the sum of weighted completion times subject to release dates. A polynomial time algorithm is developed for the case when the jobs are clustered. The jobs in each cluster must be processed sequentially and...

In this paper we consider a certain aggregate production planning model. This model permits regular and overtime production and allows for backordering of goods for a number of periods. Although the discussed model can be formulated as a linear programming problem a special (noniterative) method...

Two heuristic procedures for a one-warehouse multi-retailer system are developed. Based on the accuracy desired, the first heuristic evaluates a specified number of points. The relative error is within a bound that approaches 1/(\root 2 ln 2) - 1 \approx 2.014%. The complexity of the heuristic...

This paper examines a single machine sequencing problem with a quadratic cost function of completion times. A new type of precedence relation is constructed that determines the ordering between adjacent jobs. Each pair of jobs has a critical start time, after which the precedence relation...

In this research, we consider the planning of community health schemes by non-governmental or faith-based organisations in rural areas of developing countries, from both top-down and ground level viewpoints. We conclude that both types of planning approach are valid and necessary for...

This paper considers a new variant of the two-dimensional bin packing problem where each rectangle is assigned a due date and each bin has a fixed processing time. Hence the objective is not only to minimize the number of bins, but also to minimize the maximum lateness of the rectangles. This...