Two Type Of Inventory Models With Variable Demand Rate And Algorithm Research

Theory of storage is one branch of the operational research.The deterministic inventory models are important components of the inventory theory, and they have been deep and widely studied since the EOQ models has been presented. By far, a lot of classic theories have been put forward. At the same time, because of its maturation in theory and convenience in uses,the deterministic inventory theory has been well used in practice, and has provided effective theoretic guidance to the enterprises for saving costs in their running processes.Based on the research production drawn in the past, this paper investigates two kinds of inventory models: a kind oneself circumstance not having stock space but adopting to rent stock space and have given numerical value out the validity calculating an example having testified a model and actual application being that changeable stock cost and stock affect the warehouse village model demand rate. in a model , stock cost is a piecewise function of stock time, in have given out the validity calculating an example having explained a model, however, in real life, much the place of production producing business (or selling to discuss ) oneself not having stock, for this purpose, the thesis is similar to the enterprise stock have provided theory guiding , has practical or immediate significance .This paper investigates the inventory model that paragraph demand rate division changes with time. However, the classical inventory model sometimes is to will demand speed regards as constant, the change being that need speed does not with time varies with, change needing rates in already some document Lieutenant General looks upon as only with some one function change, for example, colour TV , computer bring forth sth. new from the old such as unceasingly in developing in the real life , since science and technology is swift and violent. This kind of product is in initial process having a market acception, in process accepting step by step in market, whose demand rates assume a linearity increasing by degrees,The product is in when becoming a long range , the same kind new product debuts ding-dang that kind, owe rates need memorial inverse proportion being similar to a product type function go down, this paper has brought forward the inventory model that need leads to with piecewise change of time , the need studying has led with the stock problem that time paragraph division changes being that two steps build a model and find the solution mark therefore specifically for owing a kind a product,the first models are that need rates are in the first time intervals inner immediately Duan inner, need leads being that direct proportion function inventory model , thesis draw a document ,Use repeated function fitting to need the practice leading , use direct law to ask out order batches and the best give preferential treatment most ordering time; Second models are that need rates are in second time intervals inner immediately Duan inner, demand rates are inverse proportion type function inventory model, this paper draws the document practice , the type function intends to close need rate with inverse proportion , use inverted calculation law to find the solution , also is to lead the queen who varies to find the solution to need, In the inferior foundation, the second time interval's initial time supposition is 0, extracts the second time interval's best order time, adds on separately after again the first time interval the total time, namely for second time interval best order time. Regarding the time determination, may act according to the product the difference, the enterprise determined in the former sales empirical value, may also act according to the market the prompt response which makes to this product's demand to determine, may become this demand rate turning point two time intervals the critical points.