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71.
This paper presents a novel control approach of hybrid neuro-fuzzy (HNF) for load frequency control (LFC) of four-area power system. The advantage of this controller is that it can handle the non-linearities, and at the same time it is faster than other existing controllers. The effectiveness of proposed controller in increasing the damping of local and inter area modes of oscillation is demonstrated in four area interconnected power system. Area-1 and area-2 consist of thermal reheat power plant whereas area-3 and area-4 consist of hydro power plant. Performance evaluation is carried out by using fuzzy, ANN, ANFIS and conventional PI and PID control approaches. The performances of the controllers are simulated using MATLAB/Simulink package. The result shows that intelligent HNF controller is having improved dynamic response and at the same time faster than ANN, fuzzy and conventional PI and PID controllers. 相似文献
72.
星座图扩展(ACE)技术可以无损地降低OFDM信号的峰均比,本文的论述指出仅追求低峰均比对应的功放效率和效能并不是最好.笔者提出了OFDM信号的最佳互补累积分布函数(OCCDF)峰均比抑制方法,即考虑OFDM信号的幅度分布及出现概率,整体地评估其对放大器失真的影响,以OFDM信号放大器的效率为评估峰均比优劣的标准,在算法上以限定MER条件下得到尽可能低的功放输入功率回退(IBO)为迭代收敛目标,预见了应该存在最高功放效率意义匹配的所谓OFDM信号的最佳幅度分布.实验证实:相比原始OFDM系统,在放大基于OCCDF准则优化后的OFDM信号时,放大器获得了3.15dB的IBO性能改善,对比同等条件下单载波系统仅差0.05dB. 相似文献
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Dicho Stratiev Ivan Chavdarov Ekaterina Nikolaychuk Ivelina Shishkova Ilshat Sharafutdinov Ivailo Tankov 《Petroleum Science and Technology》2016,34(24):1939-1945
H-Oil vacuum gas oils obtained during hydrocracking of vacuum residual oils originated from the crudes Russian Export Blend, Basrah light, and Heavy Kazakh were cracked in a mixture with a hydrotreated vacuum gas oil in the LUKOIL Neftohim Burgas commercial fluid catalytic cracking (FCC) unit. Some of the H-Oil vacuum gas oils were also cracked in a laboratory FCC (ACE) unit. The results from the commercial and the laboratory tests showed that the laboratory FCC experiments in an ACE unit can be used to evaluate the effect of feed quality on the commercial FCC unit performance. The assumption that the conversion of a vacuum gas oil (VGO) blend in the fluid catalytic cracking could be considered as a linear combination of the conversion of the individual components made by other researchers was also confirmed in this study. The higher the hydrogen content in the vacuum residual oil of a crude is the higher the FCC conversion of the H-Oil VGO, obtained during hydrocracking of that high saturate vacuum residual oil, will be expected. 相似文献
75.
Alcaide-Hidalgo JM Pueyo E Polo MC Martínez-Rodríguez AJ 《Journal of food science》2007,72(7):M276-M279
ABSTRACT: The ACE inhibitory activity (IACE) and the oxygen radical absorbance capacity (ORAC-FL) values of yeast peptides isolated from a model wine during accelerated autolysis of Saccharomyces cerevisiae have been studied. Samples were taken at 6, 24, 48, 121, and 144 h of autolysis. Peptide concentration increased throughout autolysis process. Peptides were fractionated into 2 fractions: F1, constituted by hydrophilic peptides, and F2, containing hydrophobic peptides. Both IACE activity and ORAC-FL values increased during 121 h of autolysis, then decreased afterward. Peptide fraction F2 was the main fraction involved in IACE activity and ORAC-FL. 相似文献
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通过平板划线、显微镜观察、WL培养基筛选、酒精度及血管紧张素转化酶(Angiotensin converting enzyme,ACE)抑制活性测定,对野生猕猴桃酿酒酵母进行分离筛选,再利用26S rDNA D1/D2区序列分析进行分子生物学鉴定。利用该菌株对野生猕猴桃进行纯种发酵,研究不同发酵阶段中发酵醪液的ACE抑制率、酒精度及多肽浓度变化。结果表明,经分离筛选获得适于猕猴桃果酒发酵的野生酵母JM11为酿酒酵母(Saccharomyces cerevisiae),在发酵4 d时发酵醪液的ACE抑制率为(93. 0±2. 6)%,酒精度为(7. 8±0. 5)%Vol,多肽浓度为(2 652. 0±112. 4)μg/mL,说明该菌株可酿制果酒,制得的产品还具有良好的ACE抑制活性,可作为野生猕猴桃降血压型保健果酒发酵的专用菌种或选育野生猕猴桃专用菌种的出发菌株。 相似文献
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以牛乳酪蛋白为底物,先经胃蛋白酶水解,再经胰蛋白酶水解,从水解物中分离获得血管紧张素转化酶(angiotensin converting enzyme,ACE)抑制肽并确定其氨基酸序列。酪蛋白的双酶水解物经超滤和葡聚糖凝胶色谱分离,分离得到3 个组分,收集高ACE活性抑制效果组分Ⅱ和Ⅲ。采用离子色谱法分析水解片段的氨基酸组成,液相色谱-质谱法分析水解片段的氨基酸序列,采用固相合成法制备获得的短肽片段,用分光光度法检测ACE活性抑制效果。结果表明,组分Ⅱ包含缬氨酸、丝氨酸、脯氨酸、亮氨酸、苯丙氨酸、谷氨酸、天冬氨酸、酪氨酸,共8 种氨基酸,组分Ⅲ包含痕量的丝氨酸和酪氨酸;将组分Ⅱ和Ⅲ经液相色谱-质谱分析,获得8 个片段,其中,αs2-f(56~57)∶YS、αs2-f(98~107)∶YQKFPQYLQY和κ-f(52~61)∶INNQFLPYPY具有ACE活性抑制作用,其IC50值分别为11.89、11.75 μg/mL和421 μg/mL。 相似文献