Modeling and optimization of multi-layer aggregate production planning

Abstract

<p>Aggregate production planning has attracted the attention of researchers for quite a long time now; and the continued researches depict the significance and scope for improvement in this arena. Here, a multi-product, multi-level and multi-period model has been formulated to identify the required aggregate plan for meeting the forecast demand, by regulating production rates, inventory, workforce, various production costs, and other controllable variables. Several new contributing factors, such as costs related to material handling, raw material inventory and worker training have been included in the objective function and constraint equations to make the model more realistic. A case study has been presented for a cosmetics and toiletries manufacturer in Bangladesh. Eventually, the problem has been solved using Genetic Algorithm and Particle Swarm Optimization approach. The solution illustrates that the model can be applied in a real world scenario to enhance productivity and profitability.</p>

Social Sustainability in Production Planning: A Systematic Literature Review

“…Refs. [56][57][58] indicate that the productivity of employees is affected by training measures. The effects of training on productivity are formulated always in the constraints as effect modeling.…”

“…Ref. [56] directly defines training-level-dependent capacity load factors. Within the objective function, the total costs (total losses) are minimized.…”

“…In the area of employment, the focus is on limiting personnel adjustments. For this, in the constraints, the share of hiring and layoffs relative to the number of employees in the previous period [56][57][58][59] and on acceptable layoffs [63] is restricted. Furthermore, the personnel adjustments are always accounted for monetarily within the objective function by costs for hiring/firing.…”

“…With effect modeling within the constraints, social aspects are transformed into an economic objective. So far, this has been applied especially for considering that training measures affect productivity [56][57][58]69,70] and training measures are necessary to meet employee skill requirements [61,81,111]. Additionally, the energy expenditure is primarily addressed by effect modeling [64,65,71,82,86,87,90,92].…”

“…Additionally, the energy expenditure is primarily addressed by effect modeling [64,65,71,82,86,87,90,92]. Furthermore, [68] (emission of hazardous gases), as well as [56][57][58][59]63] (personnel adjustments) transform the social aspect directly within the objective function by evaluating it with a respective cost rate, and Ref. [60] derive the production quality directly in the objective function from the share of trained employees.…”