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New direction of arrival estimation method for wideband coherent signals

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Journal of Systems Engineering and Electronics 2008年第3期19卷 473-478页

作者： wang Ling Yin jihao Chen Tianqi Coll. of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

To estimate the direction-of-arrival （DOA） of wideband coherent signals, a new method by modifying the orthogonality of the projected suhspaces method is proposed. And it can deal with randomly position perturbed arrays by using the Toeplitz method. This method needn＇t the primary information of DOA for focusing matrix and the sector dividing of interpolated method, which improving the precision of estimation and reducing the computational complexity. Simulations illustrate the effectiveness of this method.

关键词： DOA estimation array signal processing orthogonal projection array perturbation wideband coherent signals

基于桥接Transformer的小样本优化鸟声识别网络

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应用声学 2024年第3期43卷 542-551页

作者：王基豪周晓彦韩智超王丽丽南京信息工程大学电子与信息工程学院南京211800

针对实际鸟类监测环境中,收集鸟声声频数据分布不均匀,导致神经网络训练不充分,分类识别测试准确率低的问题,设计了一种桥接Transformer神经网络模型。该网络首先利用原始鸟声声频信号生成短时傅里叶变换语谱图作为输入特征,之后将语谱... 详细信息

针对实际鸟类监测环境中,收集鸟声声频数据分布不均匀,导致神经网络训练不充分,分类识别测试准确率低的问题,设计了一种桥接Transformer神经网络模型。该网络首先利用原始鸟声声频信号生成短时傅里叶变换语谱图作为输入特征,之后将语谱图输入到由注意力模块和卷积模块桥接组成的Transformer网络中,完成对语谱图中全局特征和局部特征的信息交互,最后利用单层Transformer编码器实现对每一个批次样本的损失优化,得到最终的分类结果。在Birdsdata和xeno-canto鸟声数据集上进行小样本实验,分别获得了91.34%和82.63%的平均准确率,与其他鸟声识别网络进行了对比实验,验证了该网络的有效性。

关键词：鸟声识别注意力机制卷积模块 Transformer网络

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建筑废水生化处理工艺与应用技术创新研究

粘接 2024年第7期51卷 132-135页

作者：王吉浩李钟仁上海交通大学医学院附属第九人民医院上海200011 上海工程技术大学上海201620

为了提升建筑废水净化处理效果,考察了聚合氯化铝(PAC)、聚丙烯酰胺(PAM)投加量,pH值和预曝气对不同建筑废水样本进行处理的效果,对比分析了悬浮物(SS)、生化需氧量(COD)、浊度去除率的变化。结果表明,在PAC投加量为1200 mg时,COD、SS、... 详细信息

为了提升建筑废水净化处理效果,考察了聚合氯化铝(PAC)、聚丙烯酰胺(PAM)投加量,pH值和预曝气对不同建筑废水样本进行处理的效果,对比分析了悬浮物(SS)、生化需氧量(COD)、浊度去除率的变化。结果表明,在PAC投加量为1200 mg时,COD、SS、NTU去除率取得最大值。在PAM投加量为20 mg时,COD、NTU去除率取得最大值;在PAM投加量为15 mg时,SS去除率取得最大值。在pH值为5时,COD、NTU去除率取得最大值;在pH值为7时,SS去除率取得最大值。经过预曝气30 min处理后,建筑废水的COD、SS、浊度去除率都较未经过预曝气样品有所上升。

关键词：建筑废水工艺优化去除率悬浮物生化需氧量

热等静压对激光选区熔化增材制造GH3230高温合金微裂纹与组织的影响

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航空制造技术 2024年第3期67卷 55-61页

作者：王继浩刘凯歌张雪峰谢印开李怀学中国航空制造技术研究院国家级高能束流加工技术重点实验室北京100024 中国航空制造技术研究院高能束流增量制造技术与装备北京市重点实验室北京100024 中国航空制造技术研究院增材制造航空科技重点实验室北京100024

为揭示GH3230高温合金的激光选区熔化增材成形性,研究了热等静压对激光选区熔化增材制造GH3230高温合金微裂纹与组织及拉伸性能的影响。结果表明,激光选区熔化增材制造GH3230高温合金沉积态存在凝固微裂纹,该裂纹在XOY截面呈现龟裂特征,... 详细信息

为揭示GH3230高温合金的激光选区熔化增材成形性,研究了热等静压对激光选区熔化增材制造GH3230高温合金微裂纹与组织及拉伸性能的影响。结果表明,激光选区熔化增材制造GH3230高温合金沉积态存在凝固微裂纹,该裂纹在XOY截面呈现龟裂特征,在ZOY截面呈现线状;热等静压之后,激光选区熔化增材制造GH3230高温合金的一部分微裂纹可以消除,另一部分较长的微裂纹难以消除。激光选区熔化增材制造GH3230高温合金沉积态组织基本为片状固溶体组织,在晶界附近存在少量析出碳化物;热等静压之后,在晶界附近析出大量的MoWCr碳化物,而晶内析出MoWCr碳化物数量多且尺寸较小。凝固微裂纹导致激光选区熔化增材制造GH3230高温合金沉积态XY方向抗拉强度及延伸率降低,而热等静压能减小大尺寸微裂纹,消除小尺寸微裂纹及气孔,可大幅提高XY方向的抗拉强度和延伸率。

关键词：增材制造(AM) 激光选区熔化(SLM) GH3230高温合金微裂纹热等静压(HIP)

Sub-molecular features of single proteins in solution resolved with scanning tunneling microscopy

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Nano Research 2016年第9期9卷 2551-2560页

作者： jihao wang Lei Zhang Chen Hu Qingsong Liu Yubin Hou Xin Zhang Qingyou Lu High Magnetic Field Laboratory Chinese Academy of Sciences and University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

Scanning tunneling microscopy (STM) can be used to image individual biological molecules, such as proteins, in vacuum or air. This requires sample dehydration and thus may not reflect the native state of the molecule. Extensive efforts have been made to image single proteins in solution using STM; however, the images have revealed only round or oval shapes with no sub-molecular details. Here, we present the sub-molecular features of streptavidin proteins under physiological conditions using a homebuilt low-leakage-current and highstability liquid phase STM. The N-lobe, C-lobe, and C-terminal tail of the epidermal growth factor receptor kinase domains were also resolved in solution. Our results demonstrate that the structure, morphology, and dynamics of a protein molecule can be examined under physiological conditions by the STM. [Figure not available: see fulltext.] © 2016, Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

关键词： liquid-phase scanning tunneling microscopy (STM) STM imaging under physiological conditions protein molecule sub-molecular resolution

Microstructures and Properties of Biomedical Mg-Zn-Sn-Zr Rolled Alloys

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 766-773页

作者：周生刚 ZHANG Daxin XU Yang DUAN jihao LI Tao LIU Junfeng wang Peng 曹勇 Faculty of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The as-cast Mg-2.0Zn-1.5Sn-xZr(x=0,0.4,0.6,0.8,1.0 wt%)alloy was rolled with the pressure less than 5%each *** microstructure,mechanical properties,corrosion properties and biocompatibility of the alloy were *** microstructure of the alloy was observed and analyzed by scanning electron microscope,and the tensile test was carried out by universal tensile *** corrosion resistance of the alloy in Hank's solution was studied by hydrogen evolution experiment and electrochemical test,and the biocompatibility of the alloy was tested by L929 *** results show that Mg-2Zn-1.5Sn-xZr alloy has excellent mechanical *** elongation of Mg-2Zn-1.5Sn-xZr alloy decreases with the increase of Zr content,but the tensile strength first increases and then decreases with the increase of Zr *** the Zr content is 0.8 wt%,the maximum tensile strength of the alloy is 235 *** results of hydrogen evolution experiment and electrochemical analysis show that the corrosion resistance of the alloy is the best when the Zr content is 0.8 wt%,and all the five alloys have high *** conclusion,the rolled alloy has good properties and has broad application prospects in the field of biomaterials.

关键词： magnesium alloy corrosion performance mechanical properties biocompatibility

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结构形式对桥墩局部冲刷三维性态发展的影响

东南大学学报（自然科学版） 2014年第1期44卷 155-161页

作者：熊文汪吉豪叶见曙东南大学交通学院南京210096

选用基于动网格自更新技术的三维CFD冲刷模型,可以解决既有一维、二维计算研究方法的局限性以及准确性问题,对桥墩冲刷以及周边流场三维性态进行全过程动态跟踪分析.首先采用经典***实验环境以及实验数据,分别从流场、流速以及冲刷坑进... 详细信息

选用基于动网格自更新技术的三维CFD冲刷模型,可以解决既有一维、二维计算研究方法的局限性以及准确性问题,对桥墩冲刷以及周边流场三维性态进行全过程动态跟踪分析.首先采用经典***实验环境以及实验数据,分别从流场、流速以及冲刷坑进行冲刷模型的准确性验证.进而利用该数值模型分别对3种典型桥墩(单柱墩、双柱墩、排墩)周边河床的冲刷深度、冲刷坑形态以及冲刷影响区域进行数值分析,通过数据分析得出各自完全不同的冲刷发展趋势与性态特征.通过对比分析可以看出,桥墩结构形式对桥墩局部冲刷三维性态发展有着显著影响,区分桥墩结构形式对桥墩冲刷设计、理论分析以及长期监测方案设置具有相当的必要性与重要性.

关键词：桥墩结构局部冲刷冲刷深度冲刷坑形态冲刷影响区域

Magnetic effects on EGFR kinase domain revealed with liquid-phase STM at single-molecule scale

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Magnetic effects on EGFR kinase domain revealed with liquid-...

A New Capacitance Probe for Measuring the Local Moisture Content in Wet Porous Media

中国化学会第十三届全国分析化学年会

作者： jihao wang Jing Zhang Wenjie Meng Qingyou Lu High Magnetic Field Laboratory of the Chinese Academy of Sciences University of Science and Technology of China

Magnetic effects of proteins have been proposed decades ago, the behavior of isolated proteins in magnetic fields has not been directly observed [1-3]. Using the homebuilt liquid-phase scanning tunneling microscope（STM）, we investigated the native state of Epidermal Growth Factor Receptor（EGFR） molecules under physiological conditions systematically. Sub-molecular resolution images of single EGFR molecule and dynamic formation process of EGFR dimmers were obtained for the first time. Furthermore, we observed orientation of EGFR molecules in response to magnetic fields. This may interrupt inter-molecular interactions between EGFR monomers, which are critical for their activation. Our results will support the further investigations in understanding of the biological effects of magnetic fields at single-molecule scale.

关键词： scanning tunneling microscope EGFR magnetic effects

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Journal of Thermal Science 1997年第3期6卷 185-189页

作者： Han Jitian wang jihao Gong Weiping (Depart. of Power Engineering, Shandong University of Technology, Jinan 250014)Shi Mingheng Gui Keting (Depart. of Power Engineering, Southeast University, Nanjing 210096) Depart. of Power Engineering Shandong University of Technology Jinan Depart. of Power Engineering Southeast University Nanjing

A new capacitance probe is developed for measuring local moisture content in wet porous media. The measurement principle, sensor structure of the probe, dynamic response characteristics and calibration procedure are discussed in detail. The experimental results show that the probe can be used to measure the local moisture content in wet porous media.

关键词： capacitance probe local moisture content porous media heat and mass transfer