Water and nitrogen input optimization for jujube trees under surge root irrigation based on weighted grey correlation model

In order to obtain the optimal input of water and nitrogen(W&N)suitable for the jujube trees in Northern Shaanxi,12 treatments had been set in the demonstration base of micro-irrigation jujube tree of Mizhi County in 2014-2015 through field experiment of jujube trees under surge root irrigation(SRI),in which three soil moisture levels(high moisture level W1:60%-85%θ,middle moisture level W2:50%-75%θ,low moisture level W3:40%-65%θ)and four nitrogen input levels(high nitrogen F75:0.75 kg/plant,middle nitrogen F50:0.50 kg/plant,low nitrogen F25:0.25 kg/plant,no nitrogen F0:0.00 kg/plant)were set.Through analyzing the effects of different W&N inputs on the yield,net income(NI)and W&N utilization efficiency(WUE and NUE)of jujube trees and establishing a weighted grey correlation model,the optimization of W&N input for jujube trees could be achieved under SRI.Results showed that different W&N inputs had significant influences on yield,NI,WUE and NUE.Along with the increase of soil moisture content,the yield and NUE increased,while WUE decreased gradually,and the NI had the tendency to increase first and then decrease.Along with the increase of nitrogen input,the yield,NI and WUE had the tendency to increase first and then decrease while the NUE decreased significantly,and the yield,NI,WUE and NUE could not reach the maximum at the same time.Through the study on the grey correlation model of jujube tree’s comprehensive benefit based on the yield,NI,WUE and NUE,results showed the comprehensive benefit of jujube trees was significantly different when W&N input was different,and the gray correlation degree of W2F25 treatment was the highest in two years,which means that the soil moisture content of 50%-75%θand nitrogen input of 0.25 kg/plant was the optimal W&N input for jujube trees under SRI in Northern Shaanxi area.

Research Based on the Development Trend of World Language

Multicoloured languages play an irreplaceable role in the whole world as a useful communication tool. With the development of technology and science, varieties of languages have an ideal prospective tendency to evolution during the long and wonderful history. Will they be thriving or decaying? To begin with, aimed to gain general tendency about the quantity of languages' speakers, we employ the Grey prediction to capture associative curve which can be seen in Figure 1. From the trend of this vivid figure, we not only can come to the conclusion that the number of English and Chinese users tend to increase but also find that Spanish development will reach the period of stagnation. Secondly, for further improvement, we take birth rate, death rate, economic factors and the immigration into consideration and establish the language communication model. This model is deduced from the population prediction model and virus transmission model. After data normalization, the eventual curve indicates that current top-ten languages seem to be replaced by other languages. This transformation phenomenon also occurs among such top-ten languages. For instance, Hindustani will replace Spanish in the future when seen from Table 1. What's more, after predicting the migration pattern, we can draw the conclusion that some range of languages' dissemination has obvious change. As show in vivid Figure 14, we know English will popularize widely among neighboring countries such as Canada, Mexico, Cuba and Russia. Moreover, with regard to how to manage international offices' quantity and locations in the world, we construct the efficiency model with combination of the Bayes' probability theory and Fussy comprehensive assessment. As a result, we obtain 9 optimal plans to establish the international offices. Intelligible result is showed in Table 4 and Table 5. In short, our model is reasonable and feasible, which can accommodate to different situation.