Consideration of human resources in the Mixed-model Sequencing Problem with Work Overload Minimization: Legal provisions and productivity improvement

Abstract

Abstract:Beginning with a variation of the sequencing problem in a mixed-products line (MMSP-W: Mixed-Model Sequencing Problem with Workload Minimization), we propose two new models that incorporate a set of working conditions in regard with human resources of workstations on the line. These conditions come from collective agreements and therefore must be respected by both company and labor unions. The first model takes into account the saturation limit of the workstations, and the second model also includes the activation of the operators throughout the working day. Two computational experiments were carried out using a case study of the Nissan motor plant in Barcelona with two main objectives: (1) to study the repercussions of the saturation limit on the decrease in productivity on the line and (2) to evaluate the recovery of productivity on the line via both activation of operators, while maintaining the same quality in working conditions achieved by limiting the saturation, and auxiliary processors. By results we state that saturation limitation leads an important increase of work overload, which means average economic losses of 28,731.8 Euros/day. However, the productivity reduction may be counteracted by the work pace factor increase, at certain moments of workday, and/or by the incorporation of auxiliary processors into the line.Keywords: Sequencing; Mixed-product line; Work overload; Saturation; Activity factor; Manufacturing operations. PreliminariesCurrently, many production systems exist in which the manufacture or assembly of an entire product (or a subcomponent of the product) is carried out on the production line. At the same time, the increasing market requirements demand that companies offer a wide range of products with different options. This situation is commonly found in the automotive industry in which different products are manufactured and although these products belong to the same family, they have variable characteristics that require different component consumption and resource use, such as different processing times of operations. Obviously, not all vehicles share the same type of motor, and not all are equipped with the same components.Assembly lines in the automotive industry are a clear example of this type of mixedproduct lines, which are known as Mixed-model Assembly Line (MMAL). In this type of C onsideration of human resources in the Mixed-Model Sequencing Problem with Work O verload M inimization: Legal provisions and productivity improvement J. Bautista, R. Alfaro-Pozo, C. Batalla-García 2 lines, different components (seats, steering wheels, pedals, etc.) are incorporated into the vehicle body depending on the type of vehicle that is assembled at each moment. Therefore, these lines must be flexible and able to adapt to each type of product assembled in them without incurring excessive costs.In this way, to increase flexibility and reduce costs in terms of both workforce and storage, the MMALs face two basic problems: (1) the balancing of the line, known in the literature as th...

application of principle of res judicata and estopple in family law cases in Syariah court

“…Such consent agreement should be closely guided by the legal procedure and legal substance from the islamic viewpoints. Numbers of cases presented by Siti indicating the adjudication of cases on womens' right after divorce for example harta sepencarian, child maintenance, iddah maintenance drop-out on the basis of consensus reached by the paries to waived such rights which is prescribed by Islamic Law (Bautista et al, 2015;Zaini et al, 2017). Issue arose when parties i.e.…”

Pace making and worker reassignment for assembly line rebalancing

“…Minimize the number of workers Worker task assignment: a worker can start a new task after the completion of the current task [5], "Consideration of human resources in the Mixed-model Sequencing Problem with Work Overload Minimization: Legal provisions and productivity improvement" Minimize total work overload Saturation limit: relationship between time used by the operator to carry out workload and the available time to work [18], "A comparative study of exact methods for the simple assembly line balancing problem"…”

“…For a long mixed-model assembly line, an unpaced setting is more efficient than a paced setting [26]. Mixed-model assembly lines are much more prevalent than single-model or multi-model assembly lines because of mass customization [5]. Since paced assembly lines often use automated material handling (e.g., conveyor systems) and specialized workstations, it is more difficult to reassign resources (e.g., tasks and workers) in paced than in unpaced assembly lines.…”