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12 Gb/s GaAs PHEMT跨阻抗前置放大器

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电子学报 2006年第6期34卷 1156-1158页

作者：焦世龙冯暐陈堂胜范超李拂晓叶玉堂电子科技大学光电信息学院四川成都610054 南京电子器件研究所单片集成电路与模块国家级重点实验室江苏南京210016

采用0.5μm GaAs PHEMT工艺研制了一种单电源偏置光接收机跨阻抗前置放大器.放大器-3dB带宽约为9.5GHz;在50MHz^7.5GHz范围内,跨阻增益为43.5±1.5dBΩ,输入输出回波损耗均小于-10dB;带内噪声系数在4dB^6.5dB之间,由此得到的最小等效输... 详细信息

采用0.5μm GaAs PHEMT工艺研制了一种单电源偏置光接收机跨阻抗前置放大器.放大器-3dB带宽约为9.5GHz;在50MHz^7.5GHz范围内,跨阻增益为43.5±1.5dBΩ,输入输出回波损耗均小于-10dB;带内噪声系数在4dB^6.5dB之间,由此得到的最小等效输入噪声电流密度约为17.6pA/Hz;输入12Gb/s NRI伪随机序列时,放大器输出眼图清晰,眼开良好.

关键词： PHEMT 跨阻抗前置放大器

The Committee for Women and Children

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Women of China 1994年第2期 9-10页

作者： zi MING ZHAO NING

FOR a long time, many Chinese women workers appealed to the government to set up a special organization for women and children under the State Council. They believed with the women movement developing rapidly,

关键词： The Committee for Women and Children

基于LME/BME的珠江三角洲PM_(2.5)星地融合技术研究

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中国环境科学 2019年第5期39卷 1869-1878页

作者：周爽王春林孙睿汤静黄俊沈子琦北京师范大学地理科学学部遥感科学国家重点实验室北京100875 中国气象局广州热带海洋气象研究所广东广州510640 广州市气候与农业气象中心广东广州511430

收集并处理了遥感反演的气溶胶光学厚度(AOD)、归一化植被指数(NDVI)和气象数据,采用贝叶斯最大熵(BME)结合线性混合模型(LME)估算了2015年10月～2016年3月珠江三角洲地区近地表旬平均PM_(2.5)质量浓度.结果表明,LME+BME模型的预测精度... 详细信息

收集并处理了遥感反演的气溶胶光学厚度(AOD)、归一化植被指数(NDVI)和气象数据,采用贝叶斯最大熵(BME)结合线性混合模型(LME)估算了2015年10月～2016年3月珠江三角洲地区近地表旬平均PM_(2.5)质量浓度.结果表明,LME+BME模型的预测精度比LME模型有较大提升,LME+BME模型的交叉验证结果 R^2为0.751,RMSE为6.886μg/m^3,MAE为4.52μg/m^3,而LME模型的交叉验证结果 R^2为0.703,RMSE为7.546μg/m^3,MAE为4.927μg/m^3.空间分布看,PM_(2.5)高浓度地区主要集中在广州、佛山、东莞等地区,低浓度地区主要集中在肇庆、惠州、江门的南部等地区;时间变化看,PM_(2.5)污染比较严重的时间为2015年10月中旬、2015年11月下旬以及2016年3月下旬,而2015年10月上旬、2015年12月上旬和2016年1月下旬污染则相对较低.

关键词： PM2.5 MODIS AOD 线性混合模型贝叶斯最大熵珠江三角洲

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后发劣势:对后发国家发展战略的深层思考

经济问题 2007年第4期332卷 33-37页

作者：王文龙唐德善河海大学商学院南京210098

随着国内外环境的改变和后发劣势的增加,曾经是后发国家最优战略选择的日、韩模式已失去了其存在的基础,盲目模仿反而会造成政府与市场的双重失灵;而作为当前最优制度选择的西方成熟的民主市场经济加宏观调控体制,则由于国情相异太大,... 详细信息

随着国内外环境的改变和后发劣势的增加,曾经是后发国家最优战略选择的日、韩模式已失去了其存在的基础,盲目模仿反而会造成政府与市场的双重失灵;而作为当前最优制度选择的西方成熟的民主市场经济加宏观调控体制,则由于国情相异太大,后发国家难以模仿;在这种背景下,作为次优战略选择的民主宪政加自由市场模式就成为大部分后发国家当前的最佳选择。

关键词：后发劣势最优选择次优选择精英政治共和宪政

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符合认知规律的时空轨迹融合与路网生成方法

测绘学报 2015年第11期44卷 1271-1276,1284页

作者：唐炉亮刘章杨雪阚子涵李清泉董坤武汉大学测绘遥感信息工程国家重点实验室湖北武汉430079 航天恒星科技有限公司(503所) 北京100086

以行驶在城市大街小巷的出租车GPS时空轨迹数据为研究对象,研究了符合"感知—认知—经验"认知规律3层次的轨迹融合与路网生成方法,提出了基于Delaunay三角网的时空轨迹融合模型,实现了从GPS时空轨迹中对符合认知规律需求的路网信息的获... 详细信息

以行驶在城市大街小巷的出租车GPS时空轨迹数据为研究对象,研究了符合"感知—认知—经验"认知规律3层次的轨迹融合与路网生成方法,提出了基于Delaunay三角网的时空轨迹融合模型,实现了从GPS时空轨迹中对符合认知规律需求的路网信息的获取,并以武汉市出租车GPS轨迹为试验,实现了对武汉市出租车时空轨迹的融合与武汉市路网数据的生成,证明了该方法的有效性。

关键词：空间认知轨迹融合路网生成时空GPS轨迹

An active vibration control method based on energy-fuzzy for cantilever structures excited by aerodynamic loads

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Chinese Journal of Aeronautics 2021年第9期34卷 224-235页

作者： Wei LIU Weixiao LIU Mengde ZHOU Linlin tang Qinqin WANG Zhengquan WEN Zhuang YAO Xiaojing YUAN Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education Dalian University of TechnologyDalian 116024China AVIC Aerodynamics Research Institute Shenyang 110034China

In wind tunnel tests for the full-model fixed with sting,the low structural damping of the long cantilever sting results in destructive low-frequency and large-amplitude *** order to obtain high-quality wind tunnel test data and ensure the safety of wind tunnel tests,an energy-fuzzy adaptive PD(Proportion Differentiation)control method is *** method is used for active vibration control of a cantilever structure under variable aerodynamic load excitation,and real-time adjustment of parameters is achieved according to the system characteristics of vibration ***,a real-time method is proposed to estimate the real-time vibration energy through the vibration acceleration signal,and the average exciting power of aerodynamic load is obtained by deducting the part of the power contributed by the vibration suppressor from the total ***,an energy-fuzzy adaptive PD controller is proposed to achieve adaptive control to the changes of the aerodynamic ***,the subsonic and transonic experiments were carried out in wind tunnel,the results revealed that comparing to fixed gain PD controllers,the energy-fuzzy adaptive PD controller maintains higher performance.

关键词： Active vibration control Cantilever structure Fuzzy logic PD controller Vibration energy analysis

A novel approach based on metabolomics coupled with network pharmacology to explain the effect mechanisms of Danggui Buxue tang in anaemia

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Chinese Journal of Natural Medicines 2019年第4期17卷 275-290页

作者： HUA Yong-Li MA Qi YUAN zi-Wen ZHANG Xiao-Song YAO Wan-Ling JI Peng HU Jun-Jie WEI Yan-Ming College of Veterinary Medicine Gansu Agricultural University

Danggui Buxue tang(DBT) is a famous Chinese medicinal decoction. Mechanism of DBT action is wide ranging and unclear. Exploring new ways of treatment with DBT is useful. Sprague–Dawley(SD) rats were randomly divided into 3 groups including control(NC, Saline), the DBT(at a dose of 8.10 g?kg–1), and blood deficiency(BD)(Cyclophosphamide(APH)-and Cyclophosphamide(CTX)-induced anaemia). A metabolomics approach using Liquid Chromatography-Quadrupole-Time-of-Flight/Mass Spectrometry(LC/Q-TOFMS) was developed to perform the plasma metabolic profiling analysis and differential metabolites were screened according to the multivariate statistical analysis comparing the NC and BD groups, and the hub metabolites were outliers with high scores of the centrality indices. Anaemia disease-related protein target and compound of DBT databases were constructed. The TCMSP, Chem Mapper and STITCH databases were used to predict the protein targets of DBT. Using the Cytoscape 3.2.1 to establish a phytochemical component–target protein interaction network and establish a component, protein and hub metabolite protein–protein interaction(PPI) network and merging the three PPI networks basing on BisoGenet. The gene enrichment analysis was used to analyse the relationship between proteins based on the relevant genetic similarity by ClueGO. The results shown DBT effectively treated anaemia in vivo. 11 metabolic pathways are involved in the therapeutic effect of DBT in vivo; S-adenosyl-L-methionine, glycine, L-cysteine, arachidonic acid(AA) and phosphatidylcholine(PC) were screened as hub metabolites in APH-and CTX-induced anaemia. A total of 288 targets were identified as major candidates for anaemia progression. The gene-set enrichment analysis revealed that the targets are involved in iron ion binding, haemopoiesis, reactive oxygen species production, inflammation and apoptosis. The results also showed that these targets were associated with iron ion binding, haemopoiesis, ROS production, apo

关键词： Danggui Buxue tang Metabolomics Network pharmacology Anaemia

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移动集中力作用下的悬索非线性动力分析

中南林学院学报 2006年第5期26卷 38-44页

作者：陈自力唐驾时黄伟湖南大学工程力学系中南林业科技大学土木建筑与力学学院湖南长沙410004

建立了移动集中力作用下悬索的非线性方程．指出了移动集中力对悬索的影响相当于强迫激励．当移动集中力运动速度与悬索横向弹性波速度一致时．系统将发生主共振．通过多尺度法求解．得到了主共振时各阶分叉点．通过效值计算,得到了分... 详细信息

建立了移动集中力作用下悬索的非线性方程．指出了移动集中力对悬索的影响相当于强迫激励．当移动集中力运动速度与悬索横向弹性波速度一致时．系统将发生主共振．通过多尺度法求解．得到了主共振时各阶分叉点．通过效值计算,得到了分叉图．

关键词：伽辽金法多尺度法非线性振动分叉条件悬索

Accelerated alkalinity regulation and long-term dry-wet aging durability for bauxite residue remediated with biomass pyrolysis

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Journal of Environmental Sciences 2022年第1期34卷 220-228页

作者： Zhexiang He Jingju Zhou Jianwei tang Chuxuan Li Jun Jiang Wei Chen Feng Zhu Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China School of Ecology and Environment Zhengzhou UniversityZhengzhou 450001China

Biomass fermentation provides a potential route toward the ecological disposal for the bauxite residue(BR)with high alkalinity ***,how to accelerate the remediation of the alkaline problem with a long-term durability is still a big ***,we investigated the acceleration of the decomposition of straw toward organic acid species via a pyrolysis strategy as well as the pH stability during long-term dry-wet aging for the treated *** pH of pyrolytic BR at 300℃ is stabilized at around 8.90 after 70 days’dry-wet *** the aging,the main Ca-contained alkaline minerals of calcite and cancrinite are dissolved and the content of exchangeable Na+is *** pyrolysis process can decompose straw quickly and produce more organic matters that are easily degraded to fulvic and humic acid as evidenced by 3D fluorescence spectrum *** to the fermentation with straw under natural conditions,the alkalinity regulation of BR after pyrolysis is featured with shorter period and lower pH as well as long-term pH ***,the synergistic pyrolysis of BR with straw provides an alternative method to address the alkaline issues,which is conducive to promoting the soil formation of BR.

关键词： Bauxite residue Biomass Neutralization Soil formation Dry-wet aging