Pot experiments were carried out to study the effect of nitrogen application on winter wheat under different status of soil moisture, so that the key and sensitive stage of winter wheat responses to water and nitrogen...Pot experiments were carried out to study the effect of nitrogen application on winter wheat under different status of soil moisture, so that the key and sensitive stage of winter wheat responses to water and nitrogen coordination were determined. The results showed that the application of N fertilizer was more effective in early stage than in later stage, and at the lower N rates than at the higher N rates under non-irrigated conditions. N treatments had great effect on spikelet bearing number and grain number per spike, but had no effect on 1 000-grain weight; Grain yield and yield component responses to N treatment were greater under irrigated conditions than under non-irrigated conditions. The joining stage was the key and sensitive stage of winter wheat responses to water and nitrogen coordination, and the grain yield, grain number per spike and 1000-grain weight increased, when water and N Fertilizer were applied at this stage. The mechanism is that water and fertilizer supply at joining stage can speed up the growth of above-ground crops, enhance the abilities to absorb and utilize nitrogen fertilizer, and meanwhile, delay the aging of the root and keep the root vigor for a longer period.展开更多
The demand for data security schemes has increased with the significant advancement in the field of computation and communication networks.We propose a novel three-step text encryption scheme that has provable securit...The demand for data security schemes has increased with the significant advancement in the field of computation and communication networks.We propose a novel three-step text encryption scheme that has provable security against computation attacks such as key attack and statistical attack.The proposed scheme is based on the Pell sequence and elliptic curves,where at the first step the plain text is diffused to get a meaningless plain text by applying a cyclic shift on the symbol set.In the second step,we hide the elements of the diffused plain text from the attackers.For this purpose,we use the Pell sequence,a weight function,and a binary sequence to encode each element of the diffused plain text into real numbers.The encoded diffused plain text is then confused by generating permutations over elliptic curves in the third step.We show that the proposed scheme has provable security against key sensitivity attack and statistical attacks.Furthermore,the proposed scheme is secure against key spacing attack,ciphertext only attack,and known-plaintext attack.Compared to some of the existing text encryption schemes,the proposed scheme is highly secure against modern cryptanalysis.展开更多
基金supported by the Key Program(30230230)Major Program(49890330)+1 种基金Special Program for Agriculture(30070429)of National Natural Science Foundation of ChinaNational Special Foundation for Key Basic Research,China(G1999011707).
文摘Pot experiments were carried out to study the effect of nitrogen application on winter wheat under different status of soil moisture, so that the key and sensitive stage of winter wheat responses to water and nitrogen coordination were determined. The results showed that the application of N fertilizer was more effective in early stage than in later stage, and at the lower N rates than at the higher N rates under non-irrigated conditions. N treatments had great effect on spikelet bearing number and grain number per spike, but had no effect on 1 000-grain weight; Grain yield and yield component responses to N treatment were greater under irrigated conditions than under non-irrigated conditions. The joining stage was the key and sensitive stage of winter wheat responses to water and nitrogen coordination, and the grain yield, grain number per spike and 1000-grain weight increased, when water and N Fertilizer were applied at this stage. The mechanism is that water and fertilizer supply at joining stage can speed up the growth of above-ground crops, enhance the abilities to absorb and utilize nitrogen fertilizer, and meanwhile, delay the aging of the root and keep the root vigor for a longer period.
基金This research is funded through JSPS KAKENHI Grant Number 18J23484,QAU-URF 2015HEC project NRPU-7433.
文摘The demand for data security schemes has increased with the significant advancement in the field of computation and communication networks.We propose a novel three-step text encryption scheme that has provable security against computation attacks such as key attack and statistical attack.The proposed scheme is based on the Pell sequence and elliptic curves,where at the first step the plain text is diffused to get a meaningless plain text by applying a cyclic shift on the symbol set.In the second step,we hide the elements of the diffused plain text from the attackers.For this purpose,we use the Pell sequence,a weight function,and a binary sequence to encode each element of the diffused plain text into real numbers.The encoded diffused plain text is then confused by generating permutations over elliptic curves in the third step.We show that the proposed scheme has provable security against key sensitivity attack and statistical attacks.Furthermore,the proposed scheme is secure against key spacing attack,ciphertext only attack,and known-plaintext attack.Compared to some of the existing text encryption schemes,the proposed scheme is highly secure against modern cryptanalysis.
