在傳統的EOQ模式中包含了許多的假設和限制，其目的就是為了使模式簡單化，但這也使得EOQ模式很難去應用於多變的現實情況之下。譬如說，在EOQ模式中考慮所接收到的產品為100%的良品；但在一般的情況之下，產品會因為生產製程或是運輸配送等因素，多多少少會造成損壞。這些損壞的產品可以視為不良品項，然而EOQ模式中完全忽略了這個實務上會產生的假設。
Salameh和Jaber[19]在EOQ模式之中加入了不良品項的假設，並且考慮在新訂購批量到達之後會進行一個100%的品質檢驗程序。他們的目的是找出在EOQ模式包含不良品項下的最佳訂貨策略。但是，其後在Papachristos和Konstantaras[13]兩位作者合著的論文之中指出原始模式仍有一些不合理的地方。所以，於EOQ模式中考慮不良品項的假設，在模式的建構上，尚非完備，仍然有改進的空間。
本論文就是針對Salameh和Jaber[19]以及Papachristos和Konstantaras[13]所討論的模式提出適當的修正，以彌補原創考慮不足之處。最後以數值實例探討的方式來比較修正後模式的結果與以往的不同。

Even there are many assumptions and restrictions contained in the traditional EOQ model to make this model simple, the EOQ model is still hard to apply to the real-life situations. For instance, EOQ model considers the receipt of goods with 100% quality guaranteed, but the products may be defected in the production or transportation. These defective products can be regarded as imperfect items; however, EOQ model neglects this practical assumption completely.
Salameh and Jaber[19] added the assumption of items with imperfect quality to EOQ model and considered a 100% quality screening process after receiving new ordering batch. Their aim is to find an optimal order strategy under EOQ model with imperfect items. Subsequently, Papachristos and Konstantaras[13] pointed out that there still involved irrational premises in the article written by Salameh and Jaber. Therefore, the assumption of EOQ model for items with imperfect quality is incomplete, and hence there still has space to be improved.
The goal of this paper is to modify the incomplete assumptions on the models studied in papers [13] and [19], and provide some applicable revisions. At last, we compare the numerical results between the modified model and the former models.

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