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基于数字信道化和空时频分析的多网台跳频信号DOA估计

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通信学报 2009年第10期30卷 68-74页

作者：陈利虎张尔扬国防科学技术大学电子科学与工程学院湖南长沙410073

提出了一种基于数字信道化和空时频分析的多跳频信号DOA(direction of arrival)估计方法,该方法能够在欠定条件下(传感器数目小于信号数目)实现多个信号的精确测向。首先利用多相滤波器组实现数字信道化接收机的设计,然后对各子信道的... 详细信息

提出了一种基于数字信道化和空时频分析的多跳频信号DOA(direction of arrival)估计方法,该方法能够在欠定条件下(传感器数目小于信号数目)实现多个信号的精确测向。首先利用多相滤波器组实现数字信道化接收机的设计,然后对各子信道的数据进行时频分析,得到全景时频图;再在时频域提取跳频信号的有效hop,针对每个hop建立一个空时频矩阵;最后运用空时频方法估计每hop的DOA。仿真结果验证了方法的有效性。

关键词：跳频数字信道化接收机空时频分析 DOA估计

用ADuC812.发高精度多功能的动物呼吸机

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计算机工程与应用 2003年第27期39卷 141-143页

作者：傅林张建洲四川大学计算机学院成都610064

该文介绍了用ADuC812.发高精度多功能动物呼吸机的硬件及软件设计,主要讨论了系统的电路结构和系统的软件C程序逻辑,指出了SOC设计的优势,并且展望了下一步工作。

关键词：动物呼吸机 ADuC812 嵌入式系统 C语言步进电机

Novel Polymer Networks Based on Inclusion Associations between β-Cyclodextrin and Adamantyl Groups Grafted to Poly (Acrylic Acid)

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Novel Polymer Networks Based on Inclusion Associations betwe...

One Method of How to Reserve or Abandon and Understand the Exception Rule

The 12.h Asian Pacific Confederation of chemical engineering Congress

作者： Jie Wang~a Peng Liu~a Hailan Ke~a Li Zheng~a Xuhong Guo~a Li Li~b a State-Key Laboratory of chemical engineering,East{2. university of Science and Technology,Shanghai,{2. b Department of Product engineering,School of chemical engineering,East{2. university of Science and Technology,Shanghai,china

In this paper we present novel associative polymer networks based on inclusion associations between adamantyl modified poly(acrylic acid) (ADPAA) and β-cyclodextrin modified poly(a- crylic acid)(β-CDPAA).The inclusi... 详细信息

关键词： β-cyclodextrin inclusion association adamantane polymer networks

来源： cnki会议评论

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engineering Sciences 2004年第3期 79-84页

作者： Zhou Ying 1,Yang Bingru 2. (1.college of Information Science, Beijing Normal university, Beijing 100875 2.School of Information {2., university of Science and Technology Beijing, Beijing 100083)

As a special subject in the research on information diffusion mechanism in knowledge discovery field, the author presents a new method on deciding to reserve or abandon and understanding the Exception Rule, which is to analyze the changing trend of three parameters(the support, confidence and LS),combining with the analysis of the historical changing trend of the support of the former and latter part of the Rule, in order to receive the acceptable rule and help users to fully understand them, and use them appropriately. This research has a significant effect on the post-disposal of knowledge discovery and its realizability and practicability.

关键词： knowledge discovery Exception rule Support Confidence LS

基于仿真的防空导弹综合故障诊断专家系统设计

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系统工程与电子技术 2004年第6期26卷 764-767页

作者：连光耀黄考利李天刚军械工程学院导弹工程系河北石家庄050003

研究了某新型地空导弹的故障智能诊断问题,针对故障诊断知识获取的"瓶颈",提出了一种利用计算机仿真技术与人工智能技术相结合的方案,来组建针对某型导弹故障智能诊断专家系统,利用武器系统的功能模型,通过设置系统可能出现的故障,进行... 详细信息

研究了某新型地空导弹的故障智能诊断问题,针对故障诊断知识获取的"瓶颈",提出了一种利用计算机仿真技术与人工智能技术相结合的方案,来组建针对某型导弹故障智能诊断专家系统,利用武器系统的功能模型,通过设置系统可能出现的故障,进行故障仿真,并获取故障数据信息。然后对数据进行分析变换,提取故障诊断所需知识。系统中采用了多种推理方法结合的集成推理策略,可以有效提高故障诊断的可靠性。系统在模拟诊断实验中,诊断结果成功率达百分之百。系统为新型武器装备的故障智能诊断研究,提出了一个新的发展方向。

关键词：号家系统故障诊断系统仿真知识获取

Effect of Long-Term Fertilization on Organic Carbon and Nitrogen in a Subtropical Paddy Soil

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Pedosphere 2009年第6期19卷 727-734页

作者： HUANG Qian-Ru HU Feng HUANG Shan LI Hui-Xin YUAN Ying-Hong PAN Gen-Xing ZHANG Wei-Jian college of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 (China) Jiangxi Institute of Red Soils Jinxian 331717 (China) Institute of Applied Ecology Nanjing Agricultural University Nanjing 210095 (China)

A long-term experiment beginning in 1981 in Jinxian County of Jiangxi Province, subtropical china, was conducted in a paddy field under a double rice cropping system with four different fertilization regimes, including 1) no fertilizer as control (CK), 2. balanced chemical N, P, and K fertilizers (NPK), 3) organic manure using milk vetch and pig manure in the early and late rice growing season, respectively (OM), and 4) balanced chemical fertilizers combined with organic manure (NPKM). Samples (0-17 cm) of the paddy field soil, which was derived from Quaternary red clay, were collected after the late rice harvest in November 2.03 for determination of total organic carbon (TOC) and total nitrogen (TN) and fractions of organic C and N. Results showed that TOC and TN in the NPKM and OM treatments were significantly higher than those in other two treatments (CK and NPK). Application of organic manure with or without chemical fertilizers significantly increased the contents of all fractions of organic C and N, whereas chemical fertilizer application only increased the contents of occluded particulate organic C (oPOC) and amino acid N. In addition, application of organic manure significantly enhanced the proportions of free particulate organic carbon (fPOC) and oPOC in total C, and those of amino sugar N and amino acid N (P chemical fertilizer application only increased the proportions of oPOC and amino acid N (P chemical fertilizers played the most significant role in enhancing soil organic C and N quantity and quality in the paddy field studied.

关键词： chemical fertilizers double rice cropping system organic manure

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桁架结构的易损性评价及破坏场景识别研究

浙江大学学报（工学版） 2012年第9期46卷 1633-1637,1714页

作者：何江飞高博青浙江大学建筑工程学院浙江杭州310058

针对桁架结构薄弱环节和关键构件的研究,分别以传递函数阵的H2.数及杆件应变能的相对值作为衡量结构整体性能和初始干扰的参数,给出了结构易损性的量化指标,通过桁架结构算例,验证了易损性评价指标的有效性和可行性.在此基础上,基于破... 详细信息

针对桁架结构薄弱环节和关键构件的研究,分别以传递函数阵的H2.数及杆件应变能的相对值作为衡量结构整体性能和初始干扰的参数,给出了结构易损性的量化指标,通过桁架结构算例,验证了易损性评价指标的有效性和可行性.在此基础上,基于破坏场景的定义,采用最易破坏场景确定各构件的重要性系数;由最大破坏场景来确定结构破坏的最短路径,即关键路径;用最易损场景寻找结构中存在的易损路径,即薄弱环节.结合有限元软件ANSYS和数学工具MATLAB计算易损性指标,根据其大小将结构易损性进行等级划分,由倒塌和高度易损等级确定了结构的关键路径和薄弱环节,从而为桁架结构的破坏识别提供了一种新的量化评价标准.

关键词：桁架结构易损性 H2.数场景识别评价标准

Sequential Phosphorylation of Nedd1 by Cdk1 and Plk1 is required for γTuRC targeting to centrosome

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生物物理学报 2009年第S1期25卷 245-246页

作者： Xiaoyan Zhang, Qiang Chen, Qing Jiang and Chuanmao Zhang The MOE Key Laboratory of Cell Proliferation and Differentiation and the State Key Laboratory of Bio-membrane and Membrane Bio-engineering, college of Life Sciences, Peking {2., Beijing 100871, china

Nedd1 (neural precursor cell expressed, developmentally down-regulated gene 1) is an evolutionarily conserved protein that has previously been characterized as a new member

关键词： Sequential Phosphorylation of Nedd1 by Cdk1 and Plk1 is required for TuRC targeting to centrosome

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分簇ad hoc网络协同MIMO传输策略

通信学报 2012年第3期33卷 1-9页

作者：冯文江赵伟王东重庆大学通信工程学院重庆400044

对协同MIMO传输所具有的潜力进行研究,提出一种适用于分簇ad hoc网络的传输策略,包括2.主要方面:其一是加权协同节点选择算法,该算法综合考虑节点间不对称的双向信道状态、节点剩余能量和节点连接度等因素,选择最优节点的集合构成协同M... 详细信息

对协同MIMO传输所具有的潜力进行研究,提出一种适用于分簇ad hoc网络的传输策略,包括2.主要方面:其一是加权协同节点选择算法,该算法综合考虑节点间不对称的双向信道状态、节点剩余能量和节点连接度等因素,选择最优节点的集合构成协同MIMO系统;其二是虚拟节点之间虚拟链路的建立及维护机制。仿真表明,有节点选择的协同MIMO比SISO传输能获得更大的信道容量,比无节点选择的协同MIMO传输降低能耗约70%。

关键词：协同MIMO传输信道状态信息剩余能量连接度