abstract- this study aims to model optimal cultivation pattern based on the maximization of importing virtual water and social net income of major crops in marvdasht, iran. for this purpose, a linear programming model was developed considering constraints of virtual water and land limitations followed by other models to include employment restrictions. based on the findings, wheat and tomato we...

Today's competitive conditions have caused the projects to be carried out in the least possible time with limited resources. Therefore, managing and scheduling a project is a necessity for the project. The timing of a project is to specify a sequence of times for a series of related activities. According to their priority and their latency, so that between the time the project is completed and ...

BACKGROUND Influenza is a major cause of illness, disruption to daily life, and work absenteeism among healthy working adults aged between 18 and 64 years. This group is not included among the traditional priority groups for annual vaccination. Immunization rates remain low. OBJECTIVE To assess the economic implications of a strategy for annual vaccination of this group. METHODS Using the s...

The Congressional Budget Office’s analyses of the long-term effects of changes in federal fiscal policy include the effects of changes in federal budget deficits on aggregate output and income. Those effects depend on the responses of private saving and net inflows of foreign capital to changes in deficits. This paper reviews empirical estimates of those two effects and explains how changes in ...

affiliated with the Schneider Institute for Health Policy at Brandeis University, is a national initiative that works to strengthen community action, promote social change, and improve health, especially for those who are most vulnerable. The Commonwealth of Massachusetts has made a social commitment to the proposition that all residents of the state, regardless of their financial circumstances...

This article develops a set of models for the determinants of automobile fatalities with particular attention devoted to the effects of increased cell phone usage. Cell phones have been associated with both life taking and life-saving properties. However, prior statistical evaluations of the effects of cell phones have led to fragile results. We develop in this article econometric models using ...

We present a novel method for maximizing signal gain in continuously pumped silicon-waveguide Raman amplifiers made with silicon-on-insulator technology. Our method allows for pump-power depletion during Raman amplification and makes use of a variational technique. Its use leads to a system of four coupled nonlinear differential equations, whose numerical solution provides the optimal axial pro...

Combined heat and power systems are becoming more and more important, regarding their enhanced efficiency, energy saving, and environmental aspects. In the peresent study, three configurations of combined heat and power systems are intended as an alternative to separate production plant by considering environmental aspects. First and second laws of thermodynamics are adapted to the operatin...

The exergy analysis is a proper method for performance evaluation of industrial systems. A generic and detailed analysis of the GPCSs on the second gas pipeline of Iran  is made by the means of exergy. The two main improvement measures of fuel pre-heating and steam injection technologies are presented for the current conventional stations. Steady state equations regarding the second law of ther...