To deal with severe drought when water supply is insufficient hedging rule, based on hedging rule curve, is proposed. In general, in discrete hedging rules, the rationing factors have changed from a zone to another zone at once. Accordingly, this paper is an attempt to improve the conventional hedging rule to control the changes of rationing factors. In this regard, the simulation model has emp...

Hedging is widely used to mitigate severe water shortages in the operation of reservoirs during droughts. Rationing is usually instituted with one hedging policy, which is based only on one trigger, i.e., initial storage level or current water availability. It may perform poorly in balancing the benefits of a release during the current period versus those of carryover storage during future drou...

Drought is an inevitable part of the world’s climate. It occurs in wet as well as in dry regions. Therefore, planning for drought and mitigating its impacts is essential. In this study, a hedging rule is developed using the zero/one mixed integer-programming approach. Furthermore, some procedures are introduced to ease the computational burden inherent in integer programming. Hedging rules are ...

In this study a simulation-optimization model is developed for deriving operation rule-curves in drought ‎periods. To each reservoir, two rule-curves with adjustable monthly levels are introduced dividing the ‎reservoir capacity into three zones between the normal water level and minimum operation level. To each ‎zone of a reservoir and for each month of the year a hedging coefficient is introd...

A reservoir operation model of Mun Bon and Lam Chae reservoirs was developed to simulate reservoir operation using a hedging policy. A variety of common hedging forms was specified, including one-point hedging, two-point hedging and zone-based hedging. The simulated results were compared with the standard operating policy and probability based rule curve. The percentage of failure frequency, av...

background: several reservoir systems have been constructed for hydropower generation around the world. hydropower offers an economical source of electricity with reduce carbon emissions. therefore, it is such a clean and renewable source of energy. reservoirs that generate hydropower are typically operated with the goal of maximizing energy revenue. yet, reservoir systems are inefficiently ope...

In this study, optimal operation of a reservoir by incorporation the hedging policy and Bat Algorithm (BA) is investigated. The deficit in water supply dam minimized as objective function monthly releases from are determined compared three hedging-based rules. first rule, which has single decision variable, constant release considered for all 240 months period. second scenario, one fixed each m...

this study set out to investigate the similarities and differences in frequency of incidence and type of hedging devices used in research articles written by iranian and non-iranian writers. for the purposes of the study, a corpus including 40 agriculture articles in english (20 written by iranian and 20 by non-iranian writers) were selected. collection and classification of the hedging devices...

Chinese commodity futures markets have become some of the most important derivative markets worldwide. This paper studies the optimal hedge ratios on two popular contracts in China, soybeans and copper, by employing copula functions. Our empirical results suggest that the proposed copula hedging strategy outperforms the simple regression method and dynamic conditional correlation (DCC) method b...