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Numerical Simulation of Bubble Plumes and an Analysis of Their Seismic Attributes

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Journal of Ocean University of China 2017年第2期16卷 223-232页

作者： LI Canping gou limin YOU Jiachun Laboratory of Ocean Remote Sensing and Information Technology Guangdong Ocean UniversityZhanjiang 524088P.R.China School of Ocean Sciences China University of Geosciences(Beijing)Beijing 100083P.R.China School of Geophysics and Information Technology China University of Geosciences(Beijing)Beijing 100083P.R.China

To study the bubble plume's seismic response characteristics,the model of a plume water body has been built in this article using the bubble-contained medium acoustic velocity model and the stochastic medium theory based on an analysis of both the acoustic characteristics of a bubble-contained water body and the actual features of a *** finite difference method is used for forward modelling,and the single-shot seismic record exhibits the characteristics of a scattered wave field generated by a plume.A meaningful conclusion is obtained by extracting seismic attributes from the pre-stack shot gather record of a *** values of the amplitude-related seismic attributes increase greatly as the bubble content goes up,and changes in bubble radius will not cause seismic attributes to change,which is primarily observed because the bubble content has a strong impact on the plume's acoustic velocity,while the bubble radius has a weak impact on the acoustic *** above conclusion provides a theoretical reference for identifying hydrate plumes using seismic methods and contributes to further study on hydrate decomposition and migration,as well as on distribution of the methane bubble in seawater.

关键词： plume seismic attributes natural gas hydrate scattered wave numerical simulation

Further studies on the numerical simulation of bubble plumes in the cold seepage active region

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Acta Oceanologica Sinica 2016年第1期35卷 118-124页

作者： LI Canping gou limin YOU Jiachun LIU Xuewei OU Chuling Guangdong Province Key Laboratory for Coastal Ocean Variation and Disaster Prediction (GLOD) Guangdong Ocean University Laboratory of Ocean Remote Sensing and Information Technology Guangdong Ocean University School of Ocean Sciences China University of Geosciences (Beijing) School of Geophysics and Information Technology China University of Geosciences (Beijing)

Using the occurrence characteristics of bubble plumes in the South China Sea as a reference, this paper continues to study the seismic responses produced by bubble plumes in the cold seepage active region. To make the plume modelling scheme more reasonable, we modified the original modelling scheme and reconstructed a plume water body model based on the variation of its radius as bubbles rise in seawater. The plume seismic records of shot gathers were obtained by forward simulation. The seismic records of single shot show obvious characteristics of a scattering wave field and the periodic characteristics of the model. Seismic records of shot gathers were processed using prestack depth migration. The boundary of its imaging section has a good convergence effect. The migration sections can be imaged distinctly with higher accuracy. The aforementioned studies once again laid a foundation for the further study of the seismic responses produced by plumes. They also gradually probed a more suitable seismic data processing method for plumes and provided a theoretical guidance for the identification of plumes.

关键词： plume cold seepage gas hydrate scattered wave numerical simulation

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不同孔径陶瓷膜硅烷改性及油水分离性能研究

膜科学与技术 2024年第1期44卷 16-26页

作者：苟立民段丽君柯威陈献富邱鸣慧范益群南京工业大学化工学院材料化学工程国家重点实验室南京211816 南京膜材料产业技术研究院有限公司南京211800

具有低表面能的疏水陶瓷膜常用于含水油液分离,而渗透通量的提高是提升膜分离过程经济性的关键.本文通过有机硅烷接枝改性制备疏水陶瓷膜,研究硅烷改性对不同孔径陶瓷膜结构及油水分离性能的影响。以孔径为1 000 nm、100 nm、10 nm的3... 详细信息

具有低表面能的疏水陶瓷膜常用于含水油液分离,而渗透通量的提高是提升膜分离过程经济性的关键.本文通过有机硅烷接枝改性制备疏水陶瓷膜,研究硅烷改性对不同孔径陶瓷膜结构及油水分离性能的影响。以孔径为1 000 nm、100 nm、10 nm的3种陶瓷膜为研究对象,考察不同孔径陶瓷膜硅烷化改性前后膜表面微观形貌、润湿性及渗透阻力的变化,评价3种孔径疏水陶瓷膜在溶剂、酸碱等环境下的稳定性,并将3种孔径硅烷改性的陶瓷膜用于油包水乳液分离.结果表明,孔径越小的膜硅烷化改性后渗透阻力增幅越大,尤其是当孔径达到10 nm,改性前后渗透阻力相差近3倍;原膜孔径对改性膜润湿性影响不大,且均表现出良好的耐溶剂性、耐酸碱性.低压高流速的操作方式有利于提高改性膜通量;对于水含量1 000μL/L的W/O乳液,3种改性膜对水的截留率均超过93%,渗透液水含量低于70μL/L,其中1 000 nm改性膜通量最高,达375 L/(m^(2)·h),而10 nm膜更不易被污染;对于水含量10%(体积分数)的W/O乳液,1 000 nm改性膜污染非常严重,通量迅速下降为14.1 L/(m^(2)·h),而100 nm改性膜污染程度较小,通量较高.

关键词：陶瓷膜疏水表面硅烷改性油水分离

Suppressing random noise to broaden the useful bandwidth of seismic reflection data

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Applied Geophysics 2007年第1期4卷 37-44页

作者： Liu Xuewei gou limin Department of Applied Geophysics China University of Geosciences Beijing 100083 China.

The signal-to-noise ratio （SNR） of seismic reflection data in many areas is rather poor and conventional two-dimensional filters designed to suppress noise with different moveout from the signal tend to generate artifacts. We have extended a method of multichannel filtering, based on the hypothesis that signals on adjacent channels are similar, for enhancing the SNR on stacked sections. Using only the mid-range frequencies where the SNR is highest, the event trend is found for overlapping windows on the section and the average signal vector is calculated. Then the data from the full bandwidth section are projected onto the spatially varying unit similarity vectors and the results are merged for the overlapping windows. Application of the method to synthetic data containing steeply dipping events and to a stacked section for a marine 2D line has produced good results. The modifications we have introduced carry a small overhead in computing time but they should enable the method to be used effectively even on sections containing steep dips.

关键词： noise suppressing signal SNR bandwidth broadening.

中国产业结构转型升级的速度测度、时空演变与影响因素

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工业技术经济 2022年第7期41卷 59-67页

作者：苟利民中国社会科学院大学商学院北京102401

本文基于修正后Lilien指数模型,测度2010~2020年我国30个省(区、市)产业结构转型升级速度,并运用空间误差模型分析其影响因素。研究发现:产业结构转型升级速度表现为先波动提升(2010~2016年),后平稳增长(2016~2020年)的发展态势,并呈现... 详细信息

本文基于修正后Lilien指数模型,测度2010~2020年我国30个省(区、市)产业结构转型升级速度,并运用空间误差模型分析其影响因素。研究发现:产业结构转型升级速度表现为先波动提升(2010~2016年),后平稳增长(2016~2020年)的发展态势,并呈现出东-东北-西-中部地区递减的空间分布特征。产业结构转型升级速度在空间上具有明显正相关关系,“高高集聚”省(区、市)主要来自于东部地区,“低低集聚”省(区、市)则主要来自于中、西部地区。城镇化水平、科技投入、经济基础、环境规制对产业结构转型升级速度有显著正向影响,外商直接投资则对其具有显著负向影响。

关键词：产业结构转型升级速度修正后 Lilien 指数模型时空演变区域异质性空间集聚

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超级电容器用PVDC基碳电极的研究现状

材料导报 2018年第19期32卷 3309-3317页

作者：肖国庆勾黎敏丁冬海西安建筑科技大学材料与矿资学院西安710055 西安建筑科技大学材料科学与工程博士后流动站西安710055 中钢集团洛阳耐火材料研究院有限公司先进耐火材料国家重点实验室洛阳471039

碳电极是超级电容器的关键材料,在很大程度上决定了超级电容器的性能,其发展趋势是高比表面积、高堆积密度、高中孔率、高电导率、高纯度和高性价比以及良好的电解液浸润性(即"六高一良好")。目前,活性碳纤维、碳凝胶、碳纳米管、模板... 详细信息

碳电极是超级电容器的关键材料,在很大程度上决定了超级电容器的性能,其发展趋势是高比表面积、高堆积密度、高中孔率、高电导率、高纯度和高性价比以及良好的电解液浸润性(即"六高一良好")。目前,活性碳纤维、碳凝胶、碳纳米管、模板碳等各种碳材料作为超级电容器电极材料的研究均有报道,但较低的比电容和相对较低的体积密度限制了它们在高能量需求的超级电容器电极方面的实际应用。为解决上述问题,关于具有高比表面积的多孔碳材料的研究逐渐活跃起来,特别是一些免活化的制备方法如共混聚合物裂解法、微乳液模板溶胶-凝胶聚合法及模板法等。然而,共聚混合物的制备、超临界干燥、模板的去除等使以上免活化制备方法较传统方法更为复杂。用聚偏二氯乙烯(PVDC)作为前驱体制备多孔碳可实现脱氯-活化一步完成。PVDC基碳作为超级电容器电极材料的优势在于:(1)来源广、成本低;(2)PVDC高碳密度的长链构型可促进芳香环化,与小分子相比,其所需碳化能量低,制备多孔碳材料无需额外活化过程;(3)以PVDC为碳前驱体比以其他材料为前驱体制备的多孔碳材料具有较高的比电容,目前PVDC基碳电极的比电容可达400F·g^(-1)。然而,高性能超级电容器的碳电极材料既要有高比表面积,又要有与电解液离子尺寸相适应的孔径,二者彼此制约。因此,目前研究的重点是在更微观层面上实现碳材料微观结构的调控与优化。目前,超级电容器用PVDC基碳电极的制备方法可分为脱氯-活化多步法与脱氯-活法一步法。脱氯-活化多步法是将PVDC直接机械研磨或高温热解,接着在不同活化作用后得到多孔碳材料的方法。此法得到的多孔碳具有较高的比表面积,但制备过程复杂。模板法不需要额外活化作用,但仍需两步才可得到多孔结构,获得的多孔碳材料虽然具有比表面积大、孔体积大及分级孔径分布的优点,但比电容相对较低。PVDC结构特殊,在高温热解或机械研磨过程中加入强碱,可实现脱氯-活化一步完成,得到PVDC基多孔碳材料,该法工序简单,脱氯率较高,且不会破坏PVDC的固有结构。此外,PVDC连接在亚乙烯基上的氯元素活性高,与含N-/O-聚合物中的N-/O-相比更易离开基团,可在较低温度实现脱氯碳化,且脱氯后的空位对杂质原子较敏感,易实现掺杂。本文分别从PVDC脱氯-活化多步碳化、脱氯-活化一步碳化及氮掺杂三方面综述了超级电容器用PVDC基碳电极的孔结构、比表面积及电化学性能方面的研究进展,并对超级电容器用PVDC基碳电极的研究进行了展望。

关键词：聚偏二氯乙烯超级电容器碳电极多孔碳氮掺杂

Research on fault time prediction method for high speed rail BTM unit based on multi method interactive validation

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High-Speed Railway 2024年第3期2卷 164-171页

作者： limin Fu Junqiang gou Chao Sun Hanrui Li Wei Liu School of Information Science and Technology Southwest Jiaotong UniversityChengdu 611756China China Railway Signal and Communication Research and Design Institute Group Co Ltd. Beijing 100089China

The Balise Transmission Module(BTM)unit of the on-board train control system is a crucial *** to its unique installation position and complex environment,this unit has a higher fault rate within the on-board train control *** conduct fault prediction for the BTM unit based on actual fault data,this study proposes a prediction method combining reliability statistics and machine learning,and achieves the fusion of prediction results from different dimensions through multi-method interactive ***,a method for predicting equipment fault time targeting batch equipment is *** method utilizes reliability statistics to construct a model of the remaining faultless operating time distribution considering uncertainty,thereby predicting the remaining faultless operating probability of the BTM ***,considering the complexity of the BTM unit’s fault mechanism,the small sample size of fault cases,and the potential presence of multiple fault features in fault text records,an individual-oriented fault prediction method based on Bayesian-optimized Gradient Boosting Regression Tree(Bayes-GBRT)is *** method achieves better prediction results compared to linear regression algorithms and random forest regression algorithms,with an average absolute error of only 0.224 years for predicting the fault time of this type of ***,a multi-method interactive validation approach is proposed,enabling the fusion and validation of multi-dimensional *** results indicate that the predicted fault time and the actual fault time conform to a log-normal distribution,and the parameter estimation results are basically consistent,verifying the accuracy and effectiveness of the prediction *** above research findings can provide technical support for the maintenance and modification of BTM units,effectively reducing maintenance costs and ensuring the safe operation of high-speed railway,thus having practical engineering va

关键词： High speed rail BTM unit Remaining faultless operating time Machine learning Multi method interactive verification

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一种基于同步多主对等总线的通信系统

电子技术（上海） 2017年第1期46卷 33-34页

作者：缑丽敏中航工业西安航空计算技术研究所陕西西安710065

多主对等总线系统上数据冲突频率的大大增加,导致重要信息无法得到及时处理。为了解决这一问题,文章以典型的多主对等总线CAN总线为例,介绍了一种基于同步多主对等总线通信系统的设计方法,包括硬件设计和软件设计两部分,该方法的优点是... 详细信息

多主对等总线系统上数据冲突频率的大大增加,导致重要信息无法得到及时处理。为了解决这一问题,文章以典型的多主对等总线CAN总线为例,介绍了一种基于同步多主对等总线通信系统的设计方法,包括硬件设计和软件设计两部分,该方法的优点是仅在总线系统分配的时间段内发送数据,避免在总线上产生冲突,提高车载系统信息传递的可靠性。

关键词：同步多主对等总线通信系统

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一种基于双DSP的高精度AD采集系统

微型机与应用 2017年第8期36卷 16-18页

作者：缑丽敏中航工业西安航空计算技术研究所陕西西安710065

弹载计算机体积小、接口种类多,给实现高精度AD采集带来难度。介绍一种基于双DSP的高精度AD采集系统,利用主从模式双处理器架构和高精度AD采集芯片AD73360完成对目标信号的采集和实时处理。该方法具有抗干扰能力强、量化噪声小、分辨率... 详细信息

弹载计算机体积小、接口种类多,给实现高精度AD采集带来难度。介绍一种基于双DSP的高精度AD采集系统,利用主从模式双处理器架构和高精度AD采集芯片AD73360完成对目标信号的采集和实时处理。该方法具有抗干扰能力强、量化噪声小、分辨率高的优点。通过系统联试等多方验证,满足某弹载计算机系统的性能指标要求。

关键词：双DSP ADSP-2187N AD73360 AD采集