abstract background: the intracytoplasmic sperm injection procedure ending with total fertilization failure is very distressfull event for both the clinician and the patient. objective: the aim of this study was to identify independent factors which could be used to identify total fertilization failure before the day of intracytoplasmic sperm injection. materials and methods: this was a retrosp...

Economic lot size scheduling problem (ELSP) for a multi-product single machine system is a classical problem. This paper considers ELSP with budgetary constraint as an important aspect of such systems. In the real world situations the available funds for investment in inventory is limited. By adopting the common cycle time approach to ELSP, we obtain the optimal common cycle which minimizes the...

Sequencing batch reactor (SBR) technology has found many applications in industrial wastewater treatment in recent years. The aim of this study was to determine the optimal time for a cycle of the sequencing batch reactor (SBR) and evaluate the performance of a SBR for petrochemical wastewater treatment in that cycle time. The reactor was operated with a suspended biomass configuration under ae...

This study has developed a production inventory model where the cycle timeis fuzzy, the existence of defective products is assumed in each batch andproduct screening is performed both in-production and after-production.Triangular fuzzy numbers serve to model uncertainties in the cycle time, anda fuzzified total inventory profit function is created by thedefuzzifica...

In this paper we consider a single machine system that produces items part of which are defective. The defective items produced in a time period, consisting of several equal cycles, are accumulated and are all reworked in the last cycle of this period called the rework cycle. At the end of the rework cycle the whole process will start all over again. The first significant objective of this stud...

This paper presents an analytical model based on mean value analysis (MVA) technique for a probabilistic re-entrant line. The objective is to develop a solution method to determine the total cycle time of a Reflow Screening (RS) operation in a semiconductor assembly plant. The uniqueness of this operation is that it has to be borrowed from another department in order to perform the production s...

Inventory models in which the demand rate dependents on the stock- dependent are based on the common real- life observation that greater product availability tends to stimulate more sales. In this study we develop an inventory model to determine an optimal ordering policy for quantity dependent demand rate and time dependent holding cost items with delay in payments permitted by the supplier un...

objective: alpha-thalassemia is one of the most prevalent hemoglobin disorders in the world and it is a common hereditary condition caused by deletion of one or more α-globin genes. common α-thalassemia deletions like 3.7 kb, 4.2 kb, 20.5 kb and med can be detected by multiplex pcr. there are, however, some unknown deletions that can not be detected by the mentioned method or even by direct dna...

In this paper, an economic order quantity (EOQ) inventory model for a deteriorating item is developed with the following characteristics: (i) The demand rate is deterministic and two-staged, i.e., it is constant in first part of the cycle and linear function of time in the second part. (ii) Deterioration rate is time-proportional. (iii) Shortages are not allowed to occur. The o...