Author ORCID Identifier

Date Available


Year of Publication


Degree Name

Master of Science in Manufacturing Systems Engineering (MSMSE)

Document Type

Master's Thesis




Manufacturing Systems Engineering

First Advisor

Dr. Nelson Akafuah


As the global demand for automobiles has increased rapidly over the last fifty years, customers have become more particular about the characteristics of the autos they want. This change in demand, in part has pushed manufacturing to become more flexible and created a demand for alternative, more efficient processes like the High Mix Low Volume (HMLV) production of vehicles. During HMLV, manufacturers create production lot sizes and schedule to synchronize the production processes to meet customer demand on time. The demand for the automobile parts may not be uniform or parts may not be consumed by the customer immediately, Due to this variation in demand, companies avoid shortages by large production lots and storing excess inventory. However, excess inventory has to be managed differently during the production large lots. It increases the inventory holding cost; hence it is essential to know what, when and how much to produce. An excellent example of introducing controls for efficiencies is the Toyota Production System, which allows Toyota Motors to progress implement Just in Time (JIT) production, However, to achieve the JIT, needs for producing small lots have to be met.

Hence, this thesis aims to assess a lot-sizing model that focuses on how to combine the production methods of high to low demand parts one machine to achieve JIT. The method was divided in two parts; first, it assesses the variable production of high to medium demand parts within a fixed amount of time described as Fixed Period Variable Amount (FPVA). The split lot technique used to minimize the inventory. Second, parts that have assess low demand were assessed within a Fixed Amount Variable Period (FAVP).

It is proposed that a time-oriented method with the external changeover parameter can appropriately minimize the inventory of FAVP parts and avoid idling of the workforce. Also discussed the kaizen or continuous improvement approach for changeover with directed sequencing approaches to minimize longer changeover times, significant obstacle for the production of small lot production.

The outcome of the propose model is then compared with two industry lot sizing and scheduling models, conventional lot sizing and lean benchmark lot sizing. The objective of conventional model is to minimize the cost without considering and HMLV environment and external changeover parameter. The objective of the lean benchmark model is to minimize inventory without creating idle time for the workforce. The thesis also investigates the integration and working of the Kanban scheduling system in the lean benchmark model

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