in this article, dynamics of the cerebrospinal fluid (csf) was studied, using computational fluid dynamics. using mri images of two special cases, a 2-dimensional model of the ventricular system was made. csf velocity and pressure distribution in ventricular system have high importance since the flow pattern of this liquid has an important effect on intracranial pressure, i.e., icp, which has a...

In this paper, we develop a joint quality control and preventive maintenance policy for a production system producing conforming and non-conforming units. The considered system consists of one machine which must supply another production line operating on a just-in-time basis. According to the proportion l of non-conforming units observed on each lot and compared to a threshold value lm, one de...

hairy root systems are formed by transforming plant tissues with the “natural genetic engineer” agrobacterium rhizogenes. in most plants such as cichorium intybus l., hairy root cultures have proven to be an efficient system for secondary metabolites production. the effect of zinc (znso4), a heavy metal, was investigated at different concentrations (0, 1, 5 and 10 mm) on some secondary metaboli...

two different propagation procedures including aeroponics and soil systems were compared for the minitubers production in potato. the minitubers were evaluated for several quality characters. the plant materials were from three cultivars, agria, marfona and savalan. the plantlets were grown in aeroponics and soil production systems at a plant density of 100 plants per m-2 and stem length, root ...

In this paper, the hybrid production planning & control method Double Speed Single Production Line (DSSPL) is presented, modeled and its performances evaluated and compared to classical Production Planning and Control methods (PPC). DSSPL combines JIT/kanban and Material Requirement Planning for the production of different classes of products (Aand B-items based on a market or customer oriented...

Distribution of distributed generation resources in distribution systems has several advantages, including reducing losses, improving voltage profiles, reducing pollution, and increasing system reliability. However, one of the most important points regarding the placement of these resources in distribution networks is economic issues and the return on investment and the increase in profits from...

In this paper, we study an economic production quantity (EPQ) problem in which an item is produced by a single machine. We assume that the machine may fail in an exponential random time. The repair time is an exponential random variable. It is possible to satisfy the demand from an outside supplier when the machine is failed. The objective is to determine the production and order quantities in ...

We consider a production system consisting of several fabrication lines feeding an assembly station where both fabrication and assembly lines consist of multiple machine exponential workstations and the CONWIP (CONstant Work-In-Process) mechanism is used to regulate work releases. We model this system as an assembly-like queue and develop approximations for the throughput and average number of ...