In this paper a deterministic inventory model is developed when the deterioration is constant. Demand rate is a function of selling price and holding cost is taken as time dependent. The model is solved allowing shortage in inventory. The results are solved with the help of numerical example by using Mathematica 5.1. The sensitivity analysis of the solution has done with the changes of the valu...

This paper examines the economic effects of investment in developing and introducing Almond Late Flowering Cultivars (ALFC) in a period of 52 years from 1968 to 2020, developed in Sahand Horticultural Research Station (SHRS), using the economic surplus model and field survey data. ALFC make almond supply curve move less to the left when there is a chilling case, thus affect the economic surplus...

Smartphones have revolutionized how individuals use consumer electronics and consume digital goods. I examine the extent to which smartphones have substituted other digital devices and expanded overall digital consumption, and I estimate the newly generated consumer surplus. To do so, I use newly available Korean panel survey data on individuals’ digital device ownership and detailed usage. Dur...

as an industrial crop, sugar beet plays an important role in meeting domestic demand for sugar. given the higher level of imported sugar iniran, the application of protectionist policies is an approach for supplying required sugar. one of these policies is technological improvement. in order to study the effect of this policy, sugar beet supply and demand equations in 1971-2008 were fitted by t...

Food security and economic welfare strongly depend on agricultural production, the loss of this production can be a serious challenge for food security and economic welfare. Agricultural production is also influenced by environmental and climatic factors so that the variations of climatic parameters can trigger extensive fluctuations in agricultural production. This study classifies climate cha...

precipitation is one of the hydrological processes that play an important role in controlling water resources management. shortage of rain causes some problems such as lack of drinking water. due to the importance of the issue of water shortage, using modern methods to predict hydrological processes will play an important role in planning and management of water resources. therefore, in this st...