| dc.description.abstract | Taiwan is ranked in no. eighteen among water-scarce countries all over the world. In most people′s impression, there are over two thousand millimeters of rainfall in average per year in Taiwan, and there is no shortage of water in this country. However, due to the densely population, steeped mountains, concentrated rain, and the short of rivers,most of the rainwater would rapidly flow into the ocean. In February 2015, since there was lack of rain, water was limited to different operations in Taiwan. It caused impacts on agriculture like unable to irrigate drought. It did cause a great loss on the agricultural economy. Therefore, the water resources management is very important. Generally, automatic irrigation systems are fixed time in watering. However, this mechanism usually wastes water because the weather changes sometimes and there would be actually not a need to allow fee watering. Additionally, there would be a waste of human resources to check the soil moisture with irrigation water manually. As a result, we may need an irrigation system with the function of automatically detective of humidity. However, an automatically detect humidity irrigation system needs the sensor starts in a fixed time. During the period of starting the detection, the Sensor Network would cause a lot of wasted electricity for waking up at a fixed time to detect humidity to determine whether a watering is needed. Although this approach could save water and human resources, it would increase the waste of electricity in the sensor network. Therefore, the batteries of the device needed to be changed. This paper presents a method about producing a sensor network inside the sensor at a fixed time without watering. In order to help reducing power consumption and the waste of water, the sensor would be only awaked when it is necessary needed to detect the soil moisture.
There are two methods raised in this thesis. First, the sensor can measure the moisture level without a fixed time slot in the Sensor Network. The sensor could be started working automatically when moisture level of soil has reached it′s limit. Secondly, showers are worked by a formula that calculating the node of time intervals. And it would minimize the number of times and costs for showering, meanwhile keep the moisture level of soil in standard. Also, it does help saving electricity and wasting water. | en_US |