http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Jinnan Song,Jingli Yang,Jie Xiao,Ge Guo,Kyungdeok Noh,Byoung Ryong Jeong 한국원예학회 2021 한국원예학회 학술발표요지 Vol.2021 No.10
Ammonium (NH₄<SUP>+</SUP>) sensitivity of plants is an issue of agricultural and ecological importance. Excessive NH₄<SUP>+ </SUP>triggers widely-integrated impact, conferring the toxicity symptoms. Despite plant species differ in their NH₄<SUP>+</SUP> toxicity tolerance, current knowledge suggested that all plant species employ an identical pathway in nitrogen (N) uptake and assimilation. This study was conducted to get a new insight toward NH₄<SUP>+</SUP> tolerance in plants that drew comparisons with activities of key enzymes as well as contents of chemicals assessed in this pathway in two popular leafy vegetables, Korean cabbage (Brassica campestris L.) ‘Ssamchu’ and lettuce (Lactuca sativa L.) ‘Caesar green’ as the model plants. When these plants were supplied with one of three ammonium (NH₄<SUP>+</SUP>):nitrate (NO₃<SUP>-</SUP>) ratios, 100:0, 50:50 and 0:100, during a hydroponic cultivation, lettuce was relatively more tolerant, while Korean cabbage was highly sensitive, to NH₄<SUP>+</SUP>. Ammonium sensitivity was characterized by certain detrimental visual symptoms developing on the plant such as reduced plant growth, leaf chlorosis and stunted roots, and also biochemical attributes such as enhanced activities of antioxidant enzymes, decreased contents of starch, sugar and vitamin C, and decreased photosynthesis. Subsequent quantification of activities of key enzymes and contents of chemicals showed remarkably higher contents of nitrite (NO₂<SUP>-</SUP>) and lower activities of nitrite reductase (NIR) in Korean cabbage as compared to lettuce, suggesting that these two parameters may have contributed to the differences in NH₄<SUP>+</SUP> sensitivity of these two plant species.
Lu, Jinnan,Liu, Zhixiang,Zeng, Wei,Ren, Ze The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.6
The drive inverters for high-power motors often need to reduce the carrier ratio (usually by reducing the lower switching frequency) to increase its capacity. However, the low carrier ratio results in motor control performance degradation. In this paper, an inverter and a permanent magnet synchronous motor (PMSM) are integrated to establish a unified prediction model with the delay caused by sampling and modulation that cannot be ignored under a low carrier ratio. Based on this model, a new PWM predictive control suitable for low carrier ratio (PPC-LCR) is proposed, which has better stability, dynamic performance, model accuracy and robustness under a low carrier ratio. To further enhance the control accuracy of the proposed strategy, prediction errors by parameter mismatch are analyzed, and a correction method of feedbacking the last beat prediction error is proposed to compensate for model error and parameter mismatch. Finally, experimental results are presented to support theoretical analysis and the proposed strategy.
Daixi Liao,Shouming Zhong,Jinnan Luo,Xiaojun Zhang,Yongbin Yu,Qishui Zhong 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.9
This paper is concerned with stability criteria of networked control system with two additive time-varying delay components. Firstly, by separating the whole delay interval into subintervals and using a new inequality in combination with convex polyhedron method, a less conservative criterion is proposed and an approach of stabilization controller design is given based on the obtained criterion. Secondly, a congruent condition and an extended condition with the same allowable delay upper bound are respectively deduced by using two different inequalities. Finally, some numerical examples are presented to illustrate the effectiveness of the obtained method.