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Acta Oceanologica Sinica 2021年第1期40卷 43-53页

作者： haihua chen Lele Li Lei Guan College of Information Science and Engineering Ocean University of ChinaQingdao 266100China

This study cross-calibrated the brightness temperatures observed in the Arctic by using the FY-3B/MWRI L1 and the Aqua/AMSR-E *** monthly parameters of the cross-calibration were determined and evaluated using robust linear *** snow depth in case of seasonal ice was calculated by using parameters of the crosscalibration of data from the MWRI *** correlation coefficients of the H/V polarization among all channels Tb of the two sensors were higher than *** parameters of the monthly cross-calibration were useful for the snow depth retrieval using the *** from the MWRI Tb were cross-calibrated to the AMSR-E *** in the data of the two sensors were optimized to approximately 0 K through the cross-calibration,the standard deviations decreased significantly in the range of 1.32 K to 2.57 K,and the correlation coefficients were as high as 99%.An analysis of the statistical distributions of the histograms before and after cross-calibration indicated that the FY-3B/MWRI Tb data had been well ***,the results of the cross-calibration were evaluated by data on the daily average Tb at 18.7 GHz,23.8 GHz,and 36.5 GHz(V polarization),and at 89 GHz(H/V polarization),and were applied to the snow depths retrieval in the *** parameters of monthly cross-calibration were found to be effective in terms of correcting the daily average *** results of the snow depths were compared with those of the calibrated MWRI and AMSR-E *** of 0.18 cm to 0.38 cm were observed in the monthly snow depths,with the standard deviations ranging from 4.19 cm to 4.80 cm.

关键词： FY-3B AMSR-E brightness temperature(T^(b)) cross-calibration snow depth Arctic

A New Citation Recommendation Strategy Based on Term Functions in Related Studies Section

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Journal of Data and Information Science 2021年第3期6卷 75-98页

作者： haihua chen Department of Information Science University of North TexasTexas 76207USA

Purpose:Researchers frequently encounter the following problems when writing scientific articles:(1)Selecting appropriate citations to support the research idea is challenging.(2)The literature review is not conducted extensively,which leads to working on a research problem that others have well *** study focuses on citation recommendation in the related studies section by applying the term function of a citation context,potentially improving the efficiency of writing a literature ***/methodology/approach:We present nine term functions with three newly created and six identified from existing *** these term functions as labels,we annotate 531 research papers in three topics to evaluate our proposed recommendation ***25 and Word2vec with VSM are implemented as the baseline models for the *** the term function information is applied to enhance the ***:The experiments show that the term function-based methods outperform the baseline methods regarding the recall,precision,and F1-score measurement,demonstrating that term functions are useful in identifying valuable *** limitations:The dataset is insufficient due to the complexity of annotating citation functions for paragraphs in the related studies *** recent deep learning models should be performed to future validate the proposed *** implications:The citation recommendation strategy can be helpful for valuable citation discovery,semantic scientific retrieval,and automatic literature review ***/value:The proposed citation function-based citation recommendation can generate intuitive explanations of the results for users,improving the transparency,persuasiveness,and effectiveness of recommender systems.

关键词： Citation recommendation Term function Citation context Related studies section BM25 Word2vec

Retrieval of Snow Depth on Sea Ice in the Arctic Using the FengYun-3B Microwave Radiation Imager

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Journal of Ocean University of China 2019年第3期18卷 580-588页

作者： LI Lele chen haihua GUAN Lei College of Information Science and Engineering Ocean University of China

Snow on sea ice is a sensitive indicator of climate change because it plays an important role regulating surface and near surface air temperatures. Given its high albedo and low thermal conductivity, snow cover is considered a key reason for amplified warming in polar regions. This study focuses on retrieving snow depth on sea ice from brightness temperatures recorded by the Microwave Radiation Imager(MWRI) on board the FengYun(FY)-3 B satellite. After cross calibration with the Advanced Microwave Scanning Radiometer-EOS(AMSR-E) Level 2 A data from January 1 to May 31, 2011, MWRI brightness temperatures were used to calculate sea ice concentrations based on the Arctic Radiation and Turbulence Interaction Study Sea Ice(ASI) algorithm. Snow depths were derived according to the proportional relationship between snow depth and surface scattering at 18.7 and 36.5 GHz. To eliminate the influence of uncertainties in snow grain sizes and sporadic weather effects, seven-day averaged snow depths were calculated. These results were compared with snow depths from two external data sets, the IceBridge ICDIS4 and AMSR-E Level 3 Sea Ice products. The bias and standard deviation of the differences between the MWRI snow depth and IceBridge data were respectively 1.6 and 3.2 cm for a total of 52 comparisons. Differences between MWRI snow depths and AMSR-E Level 3 products showed biases ranging between-1.01 and-0.58 cm, standard deviations from 3.63 to 4.23 cm, and correlation coefficients from 0.61 to 0.79 for the different months.

关键词： MWRI AMSRE brightness temperature snow depth inter-sensor calibration sea ice concentration

Theoretical analysis for self-sharpening penetration of tungsten high-entropy alloy into steel target with elevated impact velocities

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Acta Mechanica Sinica 2021年第6期37卷 970-982,I0002页

作者： haihua chen Xianfeng Zhang Chuang Liu Wei Xiong Mengting Tan Lan-Hong Dai School of Mechanical Engineering Nanjing University of Science&TechnologyXiaolingwei 200Nanjing210094China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing101408China

The“self-sharpening”effect has been observed experimentally in the penetration of tungsten high-entropy alloy(WHEA)into steel targets in previous *** the microscopic observation of the residual WHEA long-rod projectile(LRP),the multiphase structure at micro-scale of WHEA is the key effects on self-sharpening penetration *** order to describe the distinctive penetration behavior,the interaction between micro phases is introduced to modify the hydrodynamic penetration *** yield strengths of WHEA phases are determined based on the solid solution strengthening *** with the elbow-streamline model,the self-sharpening mechanism is revealed in view of the multi-phase flow dynamics and the flow field in the deformation area of the LRP nose is characterized to depict the shear layer evolution and the shape of the LRP’s nose as well as the determination of the penetration *** self-sharpening coefficient considering the reduction of nose radius is proposed and introduced into the penetration model to calculate the depth of penetration and the penetration *** show that the multi-phase interaction at the microscopic level contributes to the inhomogeneous distribution of the WHEA *** shear layer evolution separates part of the LRP material from the nose and makes the nose radius decrease more *** is also the reason that WHEA LRPs have a pointed nose compared with the mushroom nose of WHA heavy alloy(WHA)*** calculated results agree well with the corresponding experimental data of WHA and WHEA LRPs penetrating into semi-infinite medium carbon steel targets with elevated impact velocities.

关键词： Impact dynamics Long-rod projectile Tungsten high-entropy alloy(WHEA) Self-sharpening penetration Solid solution strengthening

Multi-Source Underwater DOA Estimation Using PSO-BP Neural Network Based on High-Order Cumulant Optimization

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China Communications 2023年第12期20卷 212-229页

作者： haihua chen Jingyao Zhang Bin Jiang Xuerong Cui Rongrong Zhou Yucheng Zhang Institute of Computing Technology Chinese Academy of SciencesBeijing 100080China College of Oceanography and Space Informatics China University of Petroleum(East China)Qingdao 266580China China YITUO Group Co. LtdLuoyang 471000China

Due to the complex and changeable environment under water,the performance of traditional DOA estimation algorithms based on mathematical model,such as MUSIC,ESPRIT,etc.,degrades greatly or even some mistakes can be made because of the mismatch between algorithm model and actual environment *** addition,the neural network has the ability of generalization and mapping,it can consider the noise,transmission channel inconsistency and other factors of the objective ***,this paper utilizes Back Propagation(BP)neural network as the basic framework of underwater DOA ***,in order to improve the performance of DOA estimation of BP neural network,the following three improvements are proposed.(1)Aiming at the problem that the weight and threshold of traditional BP neural network converge slowly and easily fall into the local optimal value in the iterative process,PSO-BP-NN based on optimized particle swarm optimization(PSO)algorithm is proposed.(2)The Higher-order cumulant of the received signal is utilized to establish the training model.(3)A BP neural network training method for arbitrary number of sources is ***,the effectiveness of the proposed algorithm is proved by comparing with the state-of-the-art algorithms and MUSIC algorithm.

关键词： gaussian colored noise higher-order cumulant multiple sources particle swarm optimization(PSO)algorithm PSO-BP neural network

Intestinal Microbiota in Early Life and Its Implications on Childhood Health

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Genomics, Proteomics & Bioinformatics 2019年第1期17卷 13-25页

作者： Lu Zhuang haihua chen Sheng Zhang Jiahui Zhuang Qiuping Li Zhichun Feng Affiliated Bayi Children's Hospital The Seventh Medical Center of PLA General Hospital National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology Beijing Key Laboratory of Pediatric Organ Failure The First Clinical Academy of Dalian Medical University College of the Environment Northeast Normal University

Trillions of microbes reside in the human body and participate in multiple physiological and pathophysiological processes that affect host health throughout the life cycle. The microbiome is hallmarked by distinctive compositional and functional features across different life *** evidence has shown that microbes residing in the human body may play fundamental roles in infant development and the maturation of the immune system. Gut microbes are thought to be essential for the facilitation of infantile and childhood development and immunity by assisting in breaking down food substances to liberate nutrients, protecting against pathogens, stimulating or modulating the immune system, and exerting control over the hypothalamic–pituitary–adrenal *** review aims to summarize the current understanding of the colonization and development of the gut microbiota in early life, highlighting the recent findings regarding the role of intestinal microbes in pediatric diseases. Furthermore, we also discuss the microbiota-mediated therapeutics that can reconfigure bacterial communities to treat dysbiosis.

关键词： Intestinal microbiota Immunity Gut-brain axis Early life Diseases Microbiota manipulation

基于宽带均匀同心球阵列的低复杂度二维波达方向估计算法

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电子与信息学报 2022年第2期44卷 710-717页

作者：陈海华王沛曌南开大学电子信息与光学工程学院天津300350 天津市光电传感器与传感网络技术重点实验室天津300350

该文提出一种基于宽带均匀同心球阵列(UCSA)的2维波达方向(2D-DOA)低复杂度估计算法。该方法将宽带UCSA输出信号转换为相位模式,并对其进行频率补偿,实现近似频率不变(FI)特性,从而降低宽带信号处理的计算复杂度。为了进一步降低2D-DOA... 详细信息

该文提出一种基于宽带均匀同心球阵列(UCSA)的2维波达方向(2D-DOA)低复杂度估计算法。该方法将宽带UCSA输出信号转换为相位模式,并对其进行频率补偿,实现近似频率不变(FI)特性,从而降低宽带信号处理的计算复杂度。为了进一步降低2D-DOA估计的计算复杂度,该文提出基于FI-UCSA的降维多重信号分类(MUSIC)算法。该方法将相位模式导向向量分解为方位角和仰角相关的两个矩阵,从而把2维搜索问题简化为1维(1D)搜索,实现降维优化并降低计算复杂度。仿真结果表明,该算法计算复杂度相较于2维MUSIC算法得到了极大的降低,并且在估计精度和分辨率上均稍有改善。

关键词：二维波达方向估计频率不变均匀同心球阵列降维多重信号分类算法

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淀粉对竹荚鱼鱼糜流变性质和凝胶特性的影响

农业工程学报 2009年第5期25卷 293-298页

作者：陈海华薛长湖中国海洋大学食品科学与工程学院青岛266003

为探讨改善竹荚鱼鱼糜凝胶品质的最佳淀粉种类和添加量,利用流变仪、质构仪、扫描电镜等方法研究了不同来源的原淀粉及其添加量对竹荚鱼鱼糜流变性质和凝胶特性的影响。动态流变性质的结果表明,在加热过程中,竹荚鱼鱼糜的弹性模量G'经历... 详细信息

为探讨改善竹荚鱼鱼糜凝胶品质的最佳淀粉种类和添加量,利用流变仪、质构仪、扫描电镜等方法研究了不同来源的原淀粉及其添加量对竹荚鱼鱼糜流变性质和凝胶特性的影响。动态流变性质的结果表明,在加热过程中,竹荚鱼鱼糜的弹性模量G'经历了2个阶段的变化,首先在20～57℃时G'逐渐降低;然后在57～80℃由于凝胶网络的形成,使G'增加。添加淀粉显著影响竹荚鱼鱼糜的G'。添加淀粉能够提高竹荚鱼鱼糜的凝胶强度。添加木薯淀粉、小麦淀粉对改善竹荚鱼鱼糜凝胶品质的效果最好,其添加量为4%,竹荚鱼鱼糜凝胶的凝胶强度分别提高了158%和155%。添加淀粉能提高竹荚鱼鱼糜凝胶的持水性。在相同的添加量时,木薯淀粉和小麦淀粉对提高竹荚鱼鱼糜凝胶的持水性的效果最好。添加淀粉能显著提高竹荚鱼鱼糜凝胶的白度,但淀粉的种类和添加量对鱼糜凝胶色泽的影响不显著。

关键词：淀粉微观结构凝胶流变性质鱼糜竹荚鱼

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亲水胶体对竹荚鱼鱼糜凝胶特性的影响

农业机械学报 2009年第2期40卷 119-125页

作者：陈海华薛长湖中国海洋大学食品科学与工程学院青岛266003

研究了亲水胶体类型和添加量对竹荚鱼鱼糜凝胶特性的影响。通过对竹荚鱼鱼糜的质构特性、持水力和白度的测定,以及超微结构观察等结果表明,添加可得胶、罗望子胶、魔芋胶、卡拉胶、琼胶和CMC的鱼糜凝胶能形成均匀、致密的三维凝胶网络结... 详细信息

研究了亲水胶体类型和添加量对竹荚鱼鱼糜凝胶特性的影响。通过对竹荚鱼鱼糜的质构特性、持水力和白度的测定,以及超微结构观察等结果表明,添加可得胶、罗望子胶、魔芋胶、卡拉胶、琼胶和CMC的鱼糜凝胶能形成均匀、致密的三维凝胶网络结构,因此能显著改善竹荚鱼鱼糜的凝胶特性,其中可得胶的效果最显著,其次是罗望子胶、魔芋胶、卡拉胶;添加瓜尔胶和海藻酸钠对竹荚鱼鱼糜的凝胶特性无显著影响;添加黄原胶和果胶后形成了较疏松、网孔较大的网络结构,降低了竹荚鱼鱼糜的凝胶特性。

关键词：亲水胶体竹荚鱼鱼糜凝胶微观结构

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赣州至深圳高速铁路桥梁总体设计及技术创新

铁道标准设计 2023年第6期67卷 73-79页

作者：陈海桦中铁第四勘察设计院集团有限公司武汉430063

赣州至深圳高速铁路是京港高速铁路的重要组成部分,设计速度350 km/h,采用无砟轨道,正线长度436 km,其中桥梁占线路长度47%。介绍赣深高铁的工程概况、桥梁设计原则及其主要技术特点,并结合复杂的建设条件,提出铁路桥梁的总体设计方案... 详细信息

赣州至深圳高速铁路是京港高速铁路的重要组成部分,设计速度350 km/h,采用无砟轨道,正线长度436 km,其中桥梁占线路长度47%。介绍赣深高铁的工程概况、桥梁设计原则及其主要技术特点,并结合复杂的建设条件,提出铁路桥梁的总体设计方案、主要桥梁结构和桥梁设计创新技术。以剑潭东江特大桥(136+260+136)m四线预应力混凝土部分斜拉桥为工程背景,研究四线线间距(5.0+14+4.6)m条件下大跨桥梁的桥型方案、结构受力和桥梁变形,解决了四线宽幅斜拉桥一孔跨越通航水域的问题;开展速度160~350 km/h桥上半封闭声屏障关键技术研究。结果表明,在标准梁上采用双侧半封闭、顶部开口8 m宽的门式半封闭声屏障结构降噪效果显著;为解决线位小角度跨越运营高速铁路的问题,设计采用钢盖梁门式墩跨越、梁部侧位现浇后横向顶推的方案;对桥上设置铁路综合检测房的需求进行深入研究,创新采用了以纵横梁体系为主的桥建合一特殊结构。

关键词：高速铁路铁路桥梁斜拉桥半封闭声屏障特殊结构总体设计