water demand的用法和樣例：
例句
- Knowledge of historic and present water demands is needed to provide a factual base for predicting future water demand.
應了解過去和當前的需水量，以便為估算未來的需水量提供實施依據。 - With the restriction of water demand and supply, the objective function optimal value was calculated by sequential quadratic programming.
以需水量和可供水量為約束條件，采用序列二次規劃法求解函數最優值。
