Available onlinewww.ejaet.com European Journal of Advances in Engineering and Technology, 2017, 4 (2): 120-128 Research Article ISSN: 2394 - 658X 120 Optimum Common Frequency Routing (CFR) of JIT Systems with Time-Varying Demand and Flexible Production Capacities Chukwuedozie N Ezema 1 , Inyiama C Hyacinth 1 and Chinwuko E Chuka 2 1 Department of Electronic and Computer Engineering, NnamdiAzikiwe University, Awka, Anambra State, Nigeria 2 Department of Industrial and Production Engineering, NnamdiAzikiwe University, Awka, Anambra State, Nigeria ecnaxel@gmail.com _____________________________________________________________________________________________ ABSTRACT This study introduces a framework for optimum Common Frequency Routing (CFR) of a JIT system with time- varying demand and flexible production capacities. The system consists of components, people and machines that make useful products. The system is managed across boundaries and interfaces. The boundaries define the scope of the system or subsystem, while the interfaces control the flows through transactions. There are three flows in the JIT manufacturing system model: the flow of materials, the flow of information, and the flow of cost. These flows estab- lish the value streams. Components of the value stream can be value-add or waste, depending on the operating con- ditions. In this research work, re-design of manufacturing systems into practical optimum Just-In-Time systems will be achieved by integration of computer simulation and analysis of variance. The conventional JIT approach is most- ly applicable to static production systems and the dynamic production systems require a more practical integrated JIT approach. However, the re-design of existing dynamic systems into just-in-time systems must follow a practical path, which can be a cumbersome task. This means, a unique practical optimum Just-In-Time system that considers system’s limitations and its dynamic behavior must be designed. Keywords: Common Frequency Routing, Manufacturing System Model, Drug Process Line, Information Exchange, JIT Devices _____________________________________________________________________________________ INTRODUCTION Since the beginning of the 80’s, much attention has been focused on a Japanese manufacturing system which be- comes known in the western world as Just-In-Time (JIT). JIT concepts have focused on improvement of manufac- turing processes, reducing setup times and lot sizes, developing mistake-proof operations and using simple schedul- ing techniques. This may be seen as eliminating waste, where waste is anything other than the minimum amount of resources. Successful JIT implementation usually results in reduced costs, improved quality and smoother produc- tion flow. JIT has been credited for the economic success that has transformed Japanese firms into world class companies. However, some observers point out that there are other factors that contribute to the success including government support for industry, the Japanese management culture and the characteristics of Japanese workers. In addition, the Japanese workers are also characterized as multi-skilled workers who are able to handle various jobs without being restricted by rigid demarcation so this achieves high flexibility [1]. The JIT production concepts were firstly pio- neered at the Toyota Motor Company (TMC) by Taiichi Ohno, and later adopted by other Japanese companies. The idea of JIT was derived from the mechanisms used in American supermarkets to replenish shelves as customers withdraw goods from them [2]. This idea was then applied by Ohno at the TMC. Today many companies in the world have employed the JIT concepts. JIT in various modified forms, as a production management concept, has been adapted by western companies with considerable success. Authorities in this area are [3-5] by introducing the concepts of zero inventory, [6] by coining the 14 points for management and [7] by proposing the quality management grid. Today, many companies in the world regard JIT or its modified forms as a major component of competitive strategy.