Content area
Full text
Introduction
Humans must drink water every day to maintain homeostasis in the body. For an adult male, water may account for 60% of body weight, while for adult women and elderly individuals, water may account for 50% of their body weight.[1] Water can be lost through urine, feces, respiration, and transpiration. Under high temperature and high physical activity, the loss of body water will intensify. The Tropical Agriculture Association[2] has published water requirements for humans, animals, and irrigated crops, given in liters per year. Based on those figures, the minimum water requirement for fluid replacement for a 70-kg human in a temperate zone is 3 L/day or 42.9 mL/kg. Minimum requirements for an individual of the same size but in a tropical zone are 4.1-6 L/day or 58.6-85.7 mL/kg.
Although replenishment of water is necessary, it is difficult to accurately determine the exact value of the water, which is related to many factors. Several agencies and organizations have established recommended values for daily drinking water for evaluation and suggestion. The Dietary Reference Intakes (DRI)[3] for water are shown in [Table 1].
Table 1.
Daily water needed for different ages.
| Age | Boys/men (L/day) | Girls/women (L/day) |
| 0-6 months | 0.7 | 0.7 |
| 7-12 months | 0.8 | 0.8 |
| 1-3 years | 1.3 | 1.3 |
| 4-8 years | 1.7 | 1.7 |
| 9-13 years | 2.4 | 2.1 |
| 14-18 years | 3.3 | 2.4 |
| 19-70+ years | 3.7 | 2.7 |
The recommended values given by these agencies and organizations are all rough values. This is because the exact value of daily water intake is associated with many factors, such as age, weight, temperature, and activity. This shows that a more accurate water intake recommendation system for ensuring human health is useful and important.
Following the conventional approach to this problem presents considerable difficulties. The reason is that it is difficult to express the factors involved with exact numerical values. For example, it is difficult to use extremely precise values to describe the current temperature. Instead, people may say "Today is very hot" or "it is a little cold today." Therefore, conventional statistical methods are not suitable for constructing this recommendation system. In this article, we use the fuzzy system to build a recommended daily water intake system because fuzzy systems have unique advantages in processing such semantic data.
In this...