For a service provider facing stochastic demand growth, expansion lead times and economies of scale complicate the expansion timing and sizing decisions. We formulate a model to minimize the infinite horizon expected discounted expansion cost under a service level constraint. The service level is defined as the proportion of demand over an expansion cycle that is satisfied by available capacity...

rice comes second after wheat in iran`s food consumption economy. however iran is one of the greatest rice importer countries all over the world because of its rising population and recent growth in gdp. this paper presents an analysis of cointegration test between rice import and it`s economic factors over the period 1990-2011, employing engle-granger model. at first, dickey-fuller test shows ...

rice comes second after wheat in iran`s food consumption economy. however iran is one of the greatest rice importer countries all over the world because of its rising population and recent growth in gdp. this paper presents an analysis of cointegration test between rice import and it`s economic factors over the period 1990-2011, employing engle-granger model. at first, dickey-fuller test shows ...

In this work, optimal control theory is used to derive the optimal production rate in a manu‐ facturing system presenting the following features: the demand rate during a certain period depends on the demand rate of the previous period (dependent demand), the demand rate depends on the inventory level, items in inventory are subject to deterioration, and the firm can adopt a periodic or a conti...

Textile dye industry waste is one of the most serious problems in the environment. The dye wastes are severely deleterious to surface water bodies. The present study was an attempt for the assessment of different physicochemical parameters such as pH, temperature, Electrical Conductivity (EC), Total Solids (TS), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Dissolved Oxygen (DO), ...

There is recent trend of providing additional treatment of wastewater beyond tertiary level. The purpose is to refine water to a quality that is safe for reuse for unrestricted irrigation and other non potable uses. For this purpose Kuwait has built and operated an advanced wastewater treatment plant with present capacity of 500,000 m/d. This plant providing treatment beyond tertiary utilizes t...

This work aimed to produce hydrogen (H₂) simultaneously with pollutant removal from biodiesel wastewater by photocatalytic oxidation using a thermally-treated commercial titanium dioxide (TiO₂) photocatalyst at room temperature (~30 °C) and ambient pressure. The effects of the operating conditions, including the catalyst loading level (1-6 g/L), UV light intensity (3.52-6.64 mW/cm²), initial pH...

This paper presents a comparative life cycle assessment of cumulative energy demand (CED) and global warming potential (GWP) of four stationary battery technologies: lithium-ion, lead-acid, sodium-sulfur, and vanadium-redox-flow. The analyses were carried out for a complete utilization of their cycle life and for six different stationary applications. Due to its lower CED and GWP impacts, a qua...

Tempelmeier (2007) considers the problem of computing replenishment cycle policy parameters under non-stationary stochastic demand and service level constraints. He analyses two possible service level measures: the minimum no stock-out probability per period (α-service level) and the so called “fill rate”, that is the fraction of demand satisfied immediately from stock on hand (β-service level)...

This paper presents the results of preliminary assessment of water quality along Red Sea coast adjoining Jeddah, Saudi Arabia. Jeddah is a major city with a population of over 2.6 million and an area 1,200 km. To study the impacts, samples of the Red Sea were collected from 24 important locations near Jeddah and analyzed in the laboratory for various water quality parameters. These parameters i...