角反射器形成的强假目标干扰给反舰导弹雷达导引头目标识别带来了严峻的挑战。为提高反舰导弹雷达导引头抗冲淡式角反射器干扰能力,提出一种基于极化与高分辨距离像(high resolution range profile,HRRP)多特征融合的角反射器鉴别方法...角反射器形成的强假目标干扰给反舰导弹雷达导引头目标识别带来了严峻的挑战。为提高反舰导弹雷达导引头抗冲淡式角反射器干扰能力,提出一种基于极化与高分辨距离像(high resolution range profile,HRRP)多特征融合的角反射器鉴别方法。结合3种场景下的实验数据,首先从海杂波中提取雷达导引头目标回波信号;其次,分析了角反和舰船回波的峰值个数、径向尺寸等5个距离像特征,以及极化相关系数均值等3个极化特征。实验数据处理结果表明,舰船与单个角反特征差异明显,与阵列角反特征差异减小;然后利用支持向量机(support vector machine,SVM)方法,基于实验数据设计5组测试,分别检验了单特征和多特征融合的鉴别性能。测试结果表明,单特征鉴别方法性能不稳定,而所提出的三特征融合鉴别方法更具稳健性,在5组测试中鉴别准确率均达到92.86%以上。展开更多
In the process of protected protocol recognition,an improved AGglomerative NESting algorithm( IAGNES) with high adaptability is proposed,which is based on the AGglomerative NESting algorithm( AGNES),for the challengin...In the process of protected protocol recognition,an improved AGglomerative NESting algorithm( IAGNES) with high adaptability is proposed,which is based on the AGglomerative NESting algorithm( AGNES),for the challenging issue of how to obtain single protocol data frames from multiprotocol data frames. It can improve accuracy and efficiency by similarity between bit-stream data frames and clusters,extract clusters in the process of clustering. Every cluster obtained contains similarity evaluation index which is helpful to evaluation. More importantly,IAGNES algorithm can automatically recognize the number of cluster. Experiments on the data set published by Lincoln Laboratory shows that the algorithm can cluster the protocol data frames with high accuracy.展开更多
以护肝活性天然产物水飞蓟宾(silybin)为模板分子,甲基丙烯酸(methacrylic,MAA)为功能单体,N-异丙基丙烯酰胺(N-isopropyl acrylamide,NIPAm)为热响应单体,生物相容性壳聚糖包裹Fe 3O 4磁核作为载体,运用电子转移活化再生催化剂原子转...以护肝活性天然产物水飞蓟宾(silybin)为模板分子,甲基丙烯酸(methacrylic,MAA)为功能单体,N-异丙基丙烯酰胺(N-isopropyl acrylamide,NIPAm)为热响应单体,生物相容性壳聚糖包裹Fe 3O 4磁核作为载体,运用电子转移活化再生催化剂原子转移自由基聚合(activator regenerated by electron transfer atom transfer radical polymerization,ARGET ATRP)制备水飞蓟宾磁性分子印迹聚合物(molecularly imprinted polymers,MMIPs),并运用傅里叶变换红外光谱(fourier transform infrared spectroscopy,FT-IR)、(thermogravimetric analysis,TGA)、(scanning electron microscope,SEM)和(X-ray diffraction,XRD)对合成的磁性印迹材料进行了表征。MMIPs对水飞蓟宾的动态吸附行为可以通过准二级动力学模型解释说明。MMIPs的印迹因子γ为3.20、选择性因子α(2.636)及相对选择性因子β(2.468),反映了所合成的印迹材料对水飞蓟宾具有良好的特异性识别能力和选择性吸附能力。另外,通过八次循环利用实验,发现MMIPs的吸附量仅减少22 %,这说明了所制备的印迹材料尚具有良好的稳定性。展开更多
Air pollution is a hot issue of current research. In recent years,air quality of China shows the significantly declining tendency. To explore temporal-spatial distribution rule of air quality status of China not inclu...Air pollution is a hot issue of current research. In recent years,air quality of China shows the significantly declining tendency. To explore temporal-spatial distribution rule of air quality status of China not including Hongkong,Macao and Taiwan,air quality indexes( AQI) of 31 provincial capitals of China in 2014 were taken as research objects. By literature retrieval,data excavation,statistic analysis and logical reasoning,temporalspatial distribution rule of air quality status from 31 provincial capitals of China and its macroscopic origin were deeply studied. The results showed that: firstly,more than 80% of provincial capitals in China had the phenomenon of air quality exceeding standard to different degrees in 2014; secondly,air quality status of China showed significant spatial difference characteristics( P < 0. 05); thirdly,rapid development of the three major industries,promotion of urbanization process and growth of urban population were important causes for bad air quality of 31 provincial capitals of China.展开更多
In order to prevent and control environmental mass incidents,by comprehensively using literature research,case analysis and logical reasoning method,27 factors influencing environmental mass incidents were selected. A...In order to prevent and control environmental mass incidents,by comprehensively using literature research,case analysis and logical reasoning method,27 factors influencing environmental mass incidents were selected. Among them,15 key influencing factors were screened by Delphi-PCA-frequency analysis composite method. The key influencing factors were analyzed,and corresponding countermeasures were put forward.展开更多
基金Supported by the National Natural Science Foundation of China(No.F020704)
文摘In the process of protected protocol recognition,an improved AGglomerative NESting algorithm( IAGNES) with high adaptability is proposed,which is based on the AGglomerative NESting algorithm( AGNES),for the challenging issue of how to obtain single protocol data frames from multiprotocol data frames. It can improve accuracy and efficiency by similarity between bit-stream data frames and clusters,extract clusters in the process of clustering. Every cluster obtained contains similarity evaluation index which is helpful to evaluation. More importantly,IAGNES algorithm can automatically recognize the number of cluster. Experiments on the data set published by Lincoln Laboratory shows that the algorithm can cluster the protocol data frames with high accuracy.
文摘以护肝活性天然产物水飞蓟宾(silybin)为模板分子,甲基丙烯酸(methacrylic,MAA)为功能单体,N-异丙基丙烯酰胺(N-isopropyl acrylamide,NIPAm)为热响应单体,生物相容性壳聚糖包裹Fe 3O 4磁核作为载体,运用电子转移活化再生催化剂原子转移自由基聚合(activator regenerated by electron transfer atom transfer radical polymerization,ARGET ATRP)制备水飞蓟宾磁性分子印迹聚合物(molecularly imprinted polymers,MMIPs),并运用傅里叶变换红外光谱(fourier transform infrared spectroscopy,FT-IR)、(thermogravimetric analysis,TGA)、(scanning electron microscope,SEM)和(X-ray diffraction,XRD)对合成的磁性印迹材料进行了表征。MMIPs对水飞蓟宾的动态吸附行为可以通过准二级动力学模型解释说明。MMIPs的印迹因子γ为3.20、选择性因子α(2.636)及相对选择性因子β(2.468),反映了所合成的印迹材料对水飞蓟宾具有良好的特异性识别能力和选择性吸附能力。另外,通过八次循环利用实验,发现MMIPs的吸附量仅减少22 %,这说明了所制备的印迹材料尚具有良好的稳定性。
基金Supported by Key Project of Humanities and Social Sciences Research,Henan Provincial Department of Education(2015-ZD-029)
文摘Air pollution is a hot issue of current research. In recent years,air quality of China shows the significantly declining tendency. To explore temporal-spatial distribution rule of air quality status of China not including Hongkong,Macao and Taiwan,air quality indexes( AQI) of 31 provincial capitals of China in 2014 were taken as research objects. By literature retrieval,data excavation,statistic analysis and logical reasoning,temporalspatial distribution rule of air quality status from 31 provincial capitals of China and its macroscopic origin were deeply studied. The results showed that: firstly,more than 80% of provincial capitals in China had the phenomenon of air quality exceeding standard to different degrees in 2014; secondly,air quality status of China showed significant spatial difference characteristics( P < 0. 05); thirdly,rapid development of the three major industries,promotion of urbanization process and growth of urban population were important causes for bad air quality of 31 provincial capitals of China.
基金Supported by the National Natural Science Foundation of China(41001338)Key Projects of Henan Colleges and Universities(15A610012)
文摘In order to prevent and control environmental mass incidents,by comprehensively using literature research,case analysis and logical reasoning method,27 factors influencing environmental mass incidents were selected. Among them,15 key influencing factors were screened by Delphi-PCA-frequency analysis composite method. The key influencing factors were analyzed,and corresponding countermeasures were put forward.
