An overview of design and operational issues of kanban systems

We present a literature review and classification of techniques to determine both the design parameters and kanban sequences for just-in-time manufacturing systems. We summarize the model structures, decision variables, performance measures and assumptions in a tabular format. It is important to state that there is a significant relationship between the design parameters, such as the number of kanbans and kanban sizes, and the scheduling decisions in a multiitem, multi-stage, multi-horizon kanban system. An experimental design is developed to evaluate the impact of operational issues, such as sequencing rules and actual lead times on the design parameters.     

Robust nonlinear control strategy to maximize energy capture in a variable speed wind turbine with an internal induction generator

This paper proposes a control strategy to maximize the wind energy captured in a variable speed wind turbine,with an internal induction generator,at low to medium wind speeds.The proposed strategy cont...     

Interaction of design and operational parameters in periodic review kanban systems

In this study, we propose an analytical model to determine the withdrawal cycle length, kanban sizes and number of kanbans simultaneously in a multi-item, multi-stage, multi-period, capacitated periodic review kanban system. Traditionally, research in kanban systems has been separated into 'design level' research, and 'shop floor level' research. In both veins of research, especially for the design level, various algorithms have been developed. However, it is important to state that there is a significant relationship between the design parameters and the operational issues, such as kanban schedules and actual lead times. Therefore, we analytically consider the interdependencies between the design and operational decisions, and evaluate their impact on each other.     

A BEM approach to model heat flow during crystallization

In most polymer processing applications such as injection moulding, fibre spinning and extrusion, crystallization plays an important role. The energy flow at the solid-liquid interface during crystallization controls the kinetics and subsequently influences the morphology of the transforming material. Our approach is based on the classical phase-change problem. The governing transient heat conduction equations in the liquid and the solid domains are solved using a boundary element method (BEM) with a time dependent fundamental solution to determine the temperature distribution. The boundary energy equation is used to predict the movement of the front. The crystallization kinetics are introduced through a mathematical model based on the cooling rate of a hypothetical control volume in the solid (crystalline) domain and the changes in the crystallinity are expressed in terms of the varying interface temperature. First, we verified the BEM formulation and implementation by comparing the results of two examples with an analytical and a finite difference method in one-dimension. Next, we investigated the effects of the crystallization kinetics by allowing the interface temperature to vary during the crystallization process. The results show that the crystallization front movement is slowed considerably when the kinetics are taken into account. Also, depending on the cooling rate and the parameters in the kinetics model, there may be undercooling during the process.