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THE CANARD-WING INTERFERENCE AND STALL SAFETY OF LIGHT CANARD AIRCRAFT

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Chinese Journal of Aeronautics 1991年第2期6卷 226-234页

作者： Bai Zhenzhu Xie Xiaobin Nanjing Aeronautical Institute Nanjing 210016, P.R.C

In this article, the interference between canard and wing is discussed on the basis of wind-tunnel test, with a brief review of the development of aerodynamic configurations of AD-100 / 200 (two light canard aircraft designed by NAI) .The safety against stall of a canard is also discussed based upon flight *** rule 'canard stall first'is introduced as an effective measure to improve safety against stall. It has been pointed out that the rule may threaten the flight safety at low-altitude. Finally,what a designer can do to remove the threat is presented.

关键词： In than THE CANARD-WING INTERFERENCE AND STALL SAFETY OF LIGHT CANARD AIRCRAFT down aoa

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MIMO雷达约束总体最小二乘改进算法

系统工程与电子技术 2009年第2期31卷 319-322页

作者：曲毅廖桂生李军姜晖西安电子科技大学雷达信号处理重点实验室陕西西安710071 武警工程学院通信工程系陕西西安710086

针对多输入多输出MIMO雷达目标定位系统中基于最小二乘算法的aoa定位精度低的缺点,分析出造成这一缺点的原因是系数矩阵存在误差。进而利用系数矩阵误差存在相关性的特点,提出用约束总体最小二乘法进行目标定位,推导了定位均方误差公式... 详细信息

针对多输入多输出MIMO雷达目标定位系统中基于最小二乘算法的aoa定位精度低的缺点,分析出造成这一缺点的原因是系数矩阵存在误差。进而利用系数矩阵误差存在相关性的特点,提出用约束总体最小二乘法进行目标定位,推导了定位均方误差公式。计算机仿真证明该方法比普通最小二乘法具有更好的定位性能。

关键词： MIMO雷达约束总体最小二乘 aoa 定位

子牙河水系水和沉积物好氧氨氧化微生物分布特征

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环境科学学报 2012年第12期32卷 2943-2950页

作者：王超单保庆中国科学院生态环境研究中心北京100085 中国科学院大学北京100093

采集海河流域子牙河水系河流沉积物和河流水样,分析了其好氧氨氧化微生物的分布特征,并探讨了氨氮、溶解氧和pH对其分布的影响.结果表明,沉积物中氨氧化古菌(aoa)和氨氧化细菌(AOB)丰度范围分别为1.05×105～1.18×109genecopies·g-1和... 详细信息

采集海河流域子牙河水系河流沉积物和河流水样,分析了其好氧氨氧化微生物的分布特征,并探讨了氨氮、溶解氧和pH对其分布的影响.结果表明,沉积物中氨氧化古菌(aoa)和氨氧化细菌(AOB)丰度范围分别为1.05×105～1.18×109genecopies·g-1和1.04×105～2.46×109genecopies·g-1,水体aoa和AOB丰度范围分别为5.21×102～2.44×109genecopies·mL-1和1.75×102～1.56×1010genecopies·mL-1;沉积物中AOB占优势,平均丰度为aoa的8.51倍,水中aoa占优势,平均丰度为AOB的18.99倍.偏相关分析表明,氨氮浓度同水中AOB与aoa丰度比值显著正相关(r=0.477,paoa丰度比值都显著正相关(r分别为0.722和0.745,p<0.01).

关键词：子牙河 aoa AOB 溶解氧氨氮 pH 分布特征

Harmonic Mitigation by Optimal Allocation of Tuned Passive Filter in Distribution System

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Energy and Power Engineering 2022年第7期14卷 291-312页

作者： Adel Abou El-Ela Sohir M. Allam Asmaa A. Mubarak Ragab A. El-Sehiemy Electrical Engineering Department Faculty of Engineering Menoufiya University Shibin El Kom Egypt South Delta Electricity Distribution Company Menoufiya Egypt Electrical Engineering Department Faculty of Engineering Kafr El Sheikh University Kafr El Sheikh Egypt

The purpose of this work is to determine the appropriate allocation of a single tuned passive filter “STPF” in a real distribution network at Tala city to prevent harmonic distortion caused by nonlinear loads. This design will cover the ideal filter parameter as well as the best filter position. The filter design is based on single and multi-objective functions that optimize the cost of the proposed filters, real power losses, total harmonic distortion “THD,” and individual harmonic distortion “IHD”. Upper and lower limitations for filter parameters, quality factor, voltage and harmonic distortion limits are determined using inequality constraints. This will be done under the equality constraint of power balance. The challenge of optimization is solved using two modern algorithms, jellyfish optimization technique “JFOT” and arithmetic optimization algorithm “aoa”, in which the placements of the filters and their parameters are selected. IEEE 33-bus radial system and an actual system as a part of the Egyptian network at Tala city are used for demonstrating the results obtained by the proposed techniques. The results reveal that the system’s harmonic distortion of current and voltage is reduced less than the limitations of the IEEE 519 standards.

关键词： Power Quality Passive Filters Harmonic Distortion Filter Parameters JFOT aoa

Effects of Wheat-Faba Bean Intercropping on Soil Microbial Community Structure in the Rhizosphere

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Agricultural Sciences 2018年第11期9卷 1389-1400页

作者： Yongbo Xu Baokun Lei Yanfeng Tang College of Tobacco Science Yunnan Agricultural University Kunming China Institute of Agricultural Environment and Resources Yunnan Academy of Agricultural Sciences Kunming China

Phospholipid fatty acids (PLFA) analysis and real-time quantitative PCR were used to investigate the effect of wheat-faba bean intercropping on soil microbial community in the rhizosphere and ammonia monooxygenase (amoA) gene abundances of ammonia-oxidizing archaea (aoa) and bacteria (AOB) at harvest stage via field trials in the red soil. We found that the bacteria and fungi of faba bean and actinomycetes of wheat in the rhizosphere showed significant (p aoa abundance between monocrops and intercrops rhizosphere, but a higher aoa abundance in the intercropping systems was found. After intercropping, the abundance of AOB in rhizosphere was significantly higher than that of aoa. Our findings suggest that wheat-faba bean intercropping may change the micro-environment and microbial community structure in the rhizosphere.

关键词： Intercropping Phospholipid Fatty Acids aoa and AOB Quantitative PCR

A New Accurately Locating Algorithm for Vehicles Positioning System Based on Ultra-wideband

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A New Accurately Locating Algorithm for Vehicles Positioning...

第十一届全国青年通信学术会议

作者：王野秋北京邮电大学

＜正＞Since the bandwidth of UWB is very large, UWB systems have excellent accuracy in terms of distance measurement and locating which are important for Intelligent Transport System （ITS）. A bi-dimensional vehicle locating system based on UWB, which only needs least two reference nodes, is designed and three algorithms based on solution-averaging ,distance-averaging and Angle of Arrival （aoa） respectively are proposed to enhance the positioning accuracy. The computer simulation result shows that the system can perform vehicle locating task with the accuracy of 0.1 - 0.6 meters which conforms to the requirement of vehicles positioning.

关键词： UWB TOA aoa positioning ranging

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宁夏第三排水沟底泥氮循环细菌群落结构特征

环境科学与技术 2024年第2期47卷 35-44页

作者：郑兰香赵靖黄凌霄宁夏大学生态环境学院宁夏银川750021 宁夏大学土木与水利工程学院宁夏银川750021 宁夏回族自治区黄河水联网数字治水重点实验室宁夏银川750021 宁夏大学信息工程学院宁夏银川750021

底泥是水体氮循环过程的重要场所。为揭示宁夏第三排水沟底泥氮循环细菌群落结构特征,该文在5个采样点底泥理化性质分析基础上,采用荧光定量PCR法测定硝化和反硝化功能基因丰度,并对细菌群落与环境因子进行相关性分析。研究结果表明:除... 详细信息

底泥是水体氮循环过程的重要场所。为揭示宁夏第三排水沟底泥氮循环细菌群落结构特征,该文在5个采样点底泥理化性质分析基础上,采用荧光定量PCR法测定硝化和反硝化功能基因丰度,并对细菌群落与环境因子进行相关性分析。研究结果表明:除三排起点底泥中pH值为6.96以外,其余点均呈弱碱性。有机碳、铵态氮、硝态氮、全氮和全磷沿沟的空间分布均呈先降低后增高趋势。在硝化菌群落中,AOB amoA基因丰度(3.16×10^(6)~7.95×10^(7)copies/g)远高于aoa amoA(5.62×10^(3)~3.76×10^(5)copies/g);反硝化菌群落中,nirS基因丰度(6.87×10^(7)~9.16×10^(8)copies/g)高于nirK(2.40×10^(7)~3.42×10^(8)copies/g)。泉古菌门是aoa主要优势菌门,变形菌门为AOB、nirK和nirS共有的主要优势菌门。底泥中的氮循环微生物群落结构与环境因素的Spearman相关性分析表明,aoa与铵态氮呈显著正相关(P<0.05),与TOC呈极显著负相关(P<0.001);AOB与pH呈显著正相关;nirS型反硝化菌与pH呈显著负相关;nirK型反硝化菌与TOC呈极显著负相关,三排底泥氮循环功能微生物群落差别较大且受理化因子影响显著。

关键词：底泥氮循环群落结构 aoa AOB nirK nirS

The Study of Factors of Interference of L1 Japanese on L2 English Pronunciation

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海外英语 2019年第12期 106-108,112页

作者：吴瑞雪 Australian National University

This article focuses on investigating whether and how the factors of aoa,exposure of L1 Japanese and motivation have an effect on the production of L2 English sound of L1 Japanese *** addition,the most effective facto... 详细信息

关键词： L1 Japanese L2 English aoa exposure motivation L1 interference L2 native-like accent

ICSI with All Oocytes Recurrent Metaphase I Characterized by Absence Perivitelline Space

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Open Journal of Obstetrics and Gynecology 2021年第9期11卷 1112-1116页

作者： Yan Jiang Ge Song Jingchuan Yuan Xuhui Zhang The Center for Reproductive Medicine and Infertility Shijiazhuang Obstetrics and Gynecology Hospital Affiliated to Hebei Medical University Shijiazhuang China

Previous cases reported recurrent all oocytes in repeated cycles were arrested at MI failed to mature after culture and ICSI resulted in total nonfertilization. Ionomycin induced first PB extrusion in patients with recurrent maturation-resistant MI oocytes. ICSI combined with assisted oocyte activation (aoa) on MII oocytes matured in vitro resulted in abnormal fertilization with no further embryo cleavage potential. The objective of this work was to research if aoa helpful to fertilization for recurrent maturation-resistant MI oocytes. In this case, patient both cycles retrievaled immature MI oocytes characterized by absence perivitelline space (APVS). In the second cycle, ionomycin was used for aoa after MI oocyte perfomed ICSI, no fertilization again.

关键词： ICSI Recurrent MI Oocyte Arrest aoa Ionomycin