Lean practices appear to have aided organisations in improving their operations, especially manufacturing companies. This paper reports on an in-depth study comparing Thai medium-size manufacturing companies who use Lean with those which have not yet adopted Lean. In this paper the word “Lean” is used to refer to “lean practices” as well as “lean strategies”. Lean methods include just-in-time (JIT), total productive maintenance (TPM), automation, value-stream mapping (VSM), Kaizen, material requirement planning (MRP), Kanban, 5S and waste elimination. Primary data were obtained through questionnaires which were analysed using a number of statistical processes including factor analysis (CFA) and structural equation modelling (SEM). Some 230 medium-sized manufacturing companies were the focal target of this study. Three latent variables, Lean (exogenous variable), product customisation (endogenous) and operational performance (endogenous) are formed in this study. There were 24 parameters and the findings provide further evidence regarding the effects which Lean practices have on product customisation and operational performance of the companies, for example. The methods for analyzing the data favour the proposed structural equation model. The results show that Lean strategies are linked to improved operational performance in the firms which practice them. Management teams in Thai medium-size manufacturing companies which have resisted Lean are encouraged to adopt Lean in order to improve operational performance, particularly in the present economic climate.

The overall objective of this paper is to present a comprehensive comparison between the EOQ model and JIT system to see either of them under which circumstances is more cost effective. There have been a few researchers dealing with the EOQ/JIT comparison model to guide companies whether or not switch to JIT or EOQ, however, their proposed models could be more realistic by taking some effective factors, such as hidden costs of a JIT system, interest rate, inflation rate, etc., into account. This research, by considering some less seen costs of both EOQ model and JIT system, develops the previous proposals of the EOQ/JIT model. This paper analyzes the impact of increasing or decreasing some determinant factors such as the interest rate, from cost perspective, to help the decision on whether or not to switch the inventory system, however, to make such a decision, companies may also take some other factors into account. A sensible link is created between the EOQ/JIT model and financial management to assure the decision makers that their financial concerns are observed in this model.

This paper explains theoretical approach of the four theories of General system Theory (GST) developed by Yourdon (1989) [Yourdon, E. (1989). Modern Structured Analysis. Yourdon Press, Prentice-Hall International, Englewood Cliffs, New Jersey. Senge] while applying it in information technology and subsequently used by caddy (2007) [Caddy I.N., & Helou, M.M. (2007). Supply chains and their management: Application of general systems theory. Journal of Retailing and Consumer Services, 14, 319–327.] in field of supply chain and management. JIT philosophy in core activities of supply chain i.e. procurement, production processes, and logistics are discussed through general system theory. The growing structure of the supply chain poses the implication restrictions and requires a heavy support system, many times a compromise is done while implementing JIT. The study would be useful to understand the general trends generated naturally regarding the adoption of the JIT philosophy in the supply chain.

Just in time is one of the most important components of having efficient production plan. The primary objective of JIT is to reduce the amount of storage as much as possible to remove the cost of inventories and work-in-progress. However, the implementation of JIT is a tedious task especially in developing countries, where there are shortages for essential infrastructures and increase the risk of production in case of JIT adaptation. In this paper, we present a survey to detect important factors preventing JIT implementation in Iran. The proposed study designs a questionnaire for assessing important factors influencing JIT adaptation, which includes inflation, political sanction, unreliable suppliers, shortage of cash flow and weak organizational culture. The results of our survey confirm that shortage of cash flow is the most important factor, follows by economical sanction and inflation.