In medium and small firm, the management system which is simple and where there is a practicality is required Ill)re than the management system which is complicated and minute of the centered around large company so that the introduction of the standard costs can be activated and it can be usefully used as a tool of management decisions. A difference between the standard costs introduction plan proposed in this paper and the preexistance study literature are as follows. In this paper, by breaking from the whole cost accounting aiming at all item, that is the traditional introduction method, and presenting the product cost accounting method by group the standards setting object was minimized and simplified. In this way, if the standards setting object is simplified, it is quick at the perimeter environment change as the little man power and flexibly it corresponds to and the cost information calculation which is exact with the setting up and maintenance of the efficient cost standard becomes available. As a result of applying for real through S corp., the usability of the method that the standard costs introduction method proposed in this paper produced the standard costs relatively short within period, it manages was verified. And the standard costs introduction method proposed in this paper went by the various cost information for each products, the management class did the management will decision which was objective and reasonable in the putting first.

Now days, the marketing environment is rapidly changed. Therefore, a lot of companies try to reduce production cost. Especially, Design is a important activities in new product development. While the concepts of design for manufacturable and concurrent engineering have made significant advances in integrating the design function with other areas in the firm. There are still major gaps in timely and accurate costing information available to designers. Inappropriate design could result in high redesign cost and delay in product relation. The generation of design and improvement is a time-consuming and mentally exhaustion process. It involves combining design features to generate as many potential design as possible. As not all features combinations are feasible, decision-makers have to narrow down the potential solutions and subsequently select appropriate design for further development. This new study is composed of 3 steps aiming at the Low Cost Design of the product. The three steps are consisted that setting up the target Cost, estimating the current functional cost, the design of a unit's reviewing according to the priority of the difference between the target cost and the functional cost.

The 5 working day's a week increase to fixed cost. Specially, the small ＆ medium size company more increase to manufacturing cost. The introduction of 5 working day's rule influence to labor cost in manufacturing cost. Also, it make disappear to fixed cost of 0.5 working day. Almost manufacturing company expect to have difficulty in product cost. The case of japan, many manufacturing company move to Asian countries after introduction of 5 working day's a week rule. The purpose of this study are the analysis of change product cost and suggest to solutions for a type of industries.