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Sparse Seismic Data Reconstruction Based on a Convolutional Neural Network Algorithm

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Journal of Ocean University of China 2023年第2期22卷 410-418页

作者： HOU Xinwei TONG Siyou wang zhongcheng XU Xiugang PENG Yin wang Kai Key Laboratory of Submarine Geosciences and Prospecting Techniques MOEOcean University of ChinaQingdao 266100China Function Laboratory of Marine Geo-Resource Evaluation and Exploration Technology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China

At present,the acquisition of seismic data is developing toward high-precision and high-density ***,complex natural environments and cultural factors in many exploration areas cause difficulties in achieving uniform and intensive acquisition,which makes complete seismic data collection ***,data reconstruction is required in the processing link to ensure imaging *** learning,as a new field in rapid development,presents clear advantages in feature extraction and *** this study,the convolutional neural network deep learning algorithm is applied to seismic data *** on the convolutional neural network algorithm and combined with the characteristics of seismic data acquisition,two training strategies of supervised and unsupervised learning are designed to reconstruct sparse acquisition seismic ***,a supervised learning strategy is proposed for labeled data,wherein the complete seismic data are segmented as the input of the training set and are randomly sampled before each training,thereby increasing the number of samples and the richness of ***,an unsupervised learning strategy based on large samples is proposed for unlabeled data,and the rolling segmentation method is used to update(pseudo)labels and training parameters in the training *** the reconstruction test of simulated and actual data,the deep learning algorithm based on a convolutional neural network shows better reconstruction quality and higher accuracy than compressed sensing based on Curvelet transform.

关键词： deep learning convolutional neural network seismic data reconstruction compressed sensing sparse collection supervised learning unsupervised learning

Dynamic Location Method for Shallow Ocean Bottom Nodes Using the Levenberg-Marquart Algorithm

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Journal of Ocean University of China 2024年第4期23卷 953-960页

作者： TONG Siyou LI Junjie XU Xiugang FANG Yunfen wang zhongcheng Key Laboratory of Submarine Geosciences and Prospecting Techniques MOEOcean University of ChinaQingdao 266100China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266237China R&D Center of BGP CNPCZhuozhou 072751China Insitute of Shengli Oilfield SINOPECDongying 257022China

Ocean bottom node(OBN)data acquisition is the main development direction of marine seismic exploration;it is widely promoted,especially in shallow sea ***,the OBN receivers may move several times because they are easily affected by tides,currents,and other factors in the shallow sea environment during long-term *** uncorrected,then the imaging quality of subsequent processing will be *** conventional secondary positioning does not consider the case of multiple movements of the receivers,and the accuracy of secondary positioning is *** first arrival wave of OBN seismic data in shallow ocean mainly comprises refracted *** this study,a nonlinear model is established in accordance with the propagation mechanism of a refracted wave and its relationship with the time interval curve to realize the accurate location of multiple receiver *** addition,the Levenberg-Marquart algorithm is used to reduce the influence of the first arrival pickup error and to automatically detect the receiver movements,identifying the accurate dynamic relocation of the *** simulation and field data show that the proposed method can realize the dynamic location of multiple receiver movements,thereby improving the accuracy of seismic imaging and achieving high practical value.

关键词： OBN dynamic location method Levenberg-Marquart algorithm seismic exploration of shallow sea

Impacts of CaO Solid Particles in Carbon Dioxide Absorption Process from Ship Emission with NaOH Solution

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Journal of Shanghai Jiaotong university(Science) 2018年第2期23卷 320-326页

作者： wang zhongcheng LIU Xiaoyu ZHOU Peilin XU Leping Merchant Marine College Shanghai Maritime University Shanghai 201306 China Naval Architecture Ocean and Marine Engineering College University of Strathclyde Glasgow G11XQ UK

CO_2 emitted from ship exhaust is one of the major sources of atmospheric pollution. In order to reduce ship CO_2 emissions, this paper comes up with the idea of recovering CO_2 from ship exhaust by Na OH solution and improves the absorption rate by adding Ca O solid particles. The effect mechanism of Ca O solid particles on CO_2 absorption efficiency is analyzed in detail, and the mathematical model is deduced and the Ca O enhancement factor is calculated through experiments. Experiment result demonstrates that the effect of CaO solid particles on the absorption of CO_2 in alkali solution is significant. The absorption rate of pure CO_2 gas,the simulated ship exhaust gas and 6135 AZG marine diesel engine emission can be increased by 10%, 15.85% and10.30%, respectively. So it can be seen that CaO solid particles play an important role in improving the absorption efficiency of ship CO_2 emission.

关键词： environmental protection diesel emissions CO2 absorption CaO particulate matter enhancement factor

Reviews on Current Carbon Emission Reduction Technologies and Projects and their Feasibilities on Ships

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Journal of Marine Science and Application 2017年第2期16卷 129-136页

作者： Haibin wang Peilin Zhou zhongcheng wang Department of Naval Architecture Ocean and Marine Engineering University of Strathclyde Glasgow G4 0LZ UK Shanghai Maritime University Merchant Marine College Shanghai 201306 China

Concern about global climate change is growing, and many projects and researchers are committed to reducing greenhouse gases from all possible sources. International Maritime Organization (IMO) has set a target of 20% CO2 reduction from shipping by 2020 and also presented a series of carbon emission reduction methods, which are known as Energy Efficiency Design Index (EEDI) and Energy Efficiency Operation Indicator (EEOI). Reviews on carbon emission reduction from all industries indicate that, Carbon Capture and Storage (CCS) is an excellent solution to global warming. In this paper, a comprehensive literature review of EEDI and EEOI and CCS is conducted and involves reviewing current policies, introducing common technologies, and considering their feasibilities for marine activities, mainly shipping. Current projects are also presented in this paper, thereby illustrating that carbon emission reduction has been the subject of attention from all over the world. Two case ship studies indicate the economic feasibility of carbon emission reduction and provide a guide for CCS system application and practical installation on ships.

关键词： marine environment control carbon reduction technologies EEDI EEOI CCS chemical absorption

The Simulation Analysis of Long-Span Membrane Structure

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Frontiers Research of Architecture and Engineering 2018年第1期1卷 22-24页

作者： zhongcheng wang yunpeng Ma School of Aeronautic Science and Engineering Beihang UniversityBeijing100871China

The analysis of wind load characteristics of gas-ribbed film structure plays an important role in the performance of the long-span membrane *** paper mainly researches on the long-span rib membrane *** wind pressure of the membrane structure is calculated by fluent,the distribution of force and surface pressure of the membrane structure under different angles and wind speeds is *** worst working condition of the wind approach angle is 60°.Maximum force angle is positively correlated with windward angle and the length of structure.

关键词： Long-Span Simulation CFD Surface pressure Windward angle

Gerhards模型在针叶木材长期寿命预测中的适用性分析

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林业科学 2021年第12期57卷 132-139页

作者：王忠铖杨娜北京交通大学土木建筑工程学院结构风工程与城市风环境北京市重点实验室北京100044

【目的】分析木材长期寿命预测中常用Gerhards模型的适用性,探讨参数选取对不同加载工况下模型预测结果的影响,同时针对木材寿命预测中预测值大于真实值的问题,提出一种基于Gerhards模型的区间预测模型分析方法,为进一步提高木材长期寿... 详细信息

【目的】分析木材长期寿命预测中常用Gerhards模型的适用性,探讨参数选取对不同加载工况下模型预测结果的影响,同时针对木材寿命预测中预测值大于真实值的问题,提出一种基于Gerhards模型的区间预测模型分析方法,为进一步提高木材长期寿命预测精度提供理论依据。【方法】首先对Gerhards模型进行理论推导,明确木材破坏时间与线性加载速度或恒定应力水平的关系;然后对比文献中针叶木材受荷试验数据真实值与8组Gerhards模型预测值,分析各模型对不同受荷形式下木材寿命预测结果的优劣;最后针对木材寿命预测中预测值大于真实值的问题,提出一种基于Gerhards模型的区间预测模型分析方法。【结果】基于Gerhards模型预测线性加载工况下木材寿命时,各模型预测值较为接近,且与试验值偏差较小;预测恒定加载工况下木材寿命时,各模型预测值间差别较大,且个别模型预测值与试验值差异极大。当木材试样为承受恒定应力水平介于60%~95%的北美花旗松时,建议采用Gerhards模型6进行寿命预测;当木材试样为承受恒定应力水平介于55%~105%的欧洲云杉时,建议采用Gerhards模型7进行寿命预测;当木材试样承受恒定应力水平小于50%时,建议采用Gerhards模型1进行寿命预测。预测模型所用数据加载工况与被预测对象受荷工况之间的差异对模型预测精度影响极大。相比传统预测模型,区间预测模型能够更完整地反映试验数据分布特征,且基于试验数据分位数拟合的预测模型较基于T分布假设拟合的预测模型涵盖更多试验数据点。【结论】分析Gerhards模型在木材长期寿命预测中的适用性十分必要,当预测模型所用数据加载工况与被预测对象受荷工况相似时,模型具有较好预测效果。本研究提出的分位数模型分析方法能够使绝大多数试验数据点落在区间模型内,可为提高木材长期寿命预测精度提供理论依据。

关键词：木材 Gerhards模型长期寿命预测适用性分析区间模型

Neuroprotective effects of subthalamic nucleus high-frequency stimulation on substantia nigra neurons in a Parkinson's disease rat model

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Neural Regeneration Research 2008年第9期3卷 1014-1017页

作者： Yu Ma zhongcheng wang Jianguo Zhang Huanguang Liu Ying Zhang Department of Functional Neurosurgery Beijing Neurosurgical Institute Capital Medical University Beijing 100050 China Department of Neurosurgery Beijing Tiantan Hospital Capital Medical University Beijing 100050 China

BACKGROUND： Deep-brain stimulation has proven to be beneficial in the treatment of Parkinson＇s disease （PD） patients. OBJECTIVE： To investigate the effects of high-frequency stimulation （HFS） to the subthalamic nucleus （STN） on neuronal apoptosis and apoptosis-related gene expression in the substantia nigra pars compacta, and to analyze the neuroprotective effect of HFS-STN. DESIGN, TIME AND SETTING： Neuronal morphology experiments were performed in the Beijing Neurosurgical Institute from May to December in 2005. MATERIALS： Forty healthy, adult, Sprague Dawley rats were used to establish a PD model with a unilateral microinjection of 6-hydroxydopamine into two target areas of the right medial forebrain bundle. 6-hydroxydopamine was purchased from Sigma （USA）; high-frequency electrical stimulator was produced by World Precision Instruments （USA）; Terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） kit was a product of Nanjing Jiancheng Technology Co., Ltd. （China）; and Bcl-2 and Bax protein assay kit were purchased from Wuhan Boster Bioengineering Co., Ltd. （China）. METHODS： Forty rats were randomly divided into three groups. The stimulation group （n = 15） received HFS-STN on the day of PD modeling. The PD model group （n = 15） was used to establish the PD model. The control group （n = 10） was injected with normal saline containing 0.2 g/L ascorbic acid into two areas of the right medial forebrain bundle. MAIN OUTCOME MEASURES： Survival of dopaminergic neurons in the substantia nigra pars compacta was determined using Nissl staining. Apoptosis of dopaminergic neurons was detected using TUNEL techniques. Expression of anti-apoptotic protein, Bcl-2, and pro-apoptotic protein, Bax, were assayed by immunohistochemistry. RESULTS： Following 6-hydroxydopamine injection, the number of substantia nigra pars compacta neurons was reduced in the stimulation and PD model groups, compared to the control group. At 2 and 4 weeks post-surgery, the grey value of Nissl

关键词： apoptosis deep-brain stimulation: high-frequency stimulation Parkinson's disease

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多测点无损检测法评估古建木材抗弯强度

湖南大学学报（自然科学版） 2022年第1期49卷 78-84页

作者：王忠铖杨娜北京交通大学土木建筑工程学院北京100044

为了提高无损检测手段预测古建木材抗弯强度的精度,用应力波仪和阻力仪对藏青杨旧材抗弯试样进行了多测点无损检测,通过对比试样抗弯强度,分析了无损指标与木材抗弯强度的相关性,讨论了测试手段、测点位置、测点数量对相关系数的影响,... 详细信息

为了提高无损检测手段预测古建木材抗弯强度的精度,用应力波仪和阻力仪对藏青杨旧材抗弯试样进行了多测点无损检测,通过对比试样抗弯强度,分析了无损指标与木材抗弯强度的相关性,讨论了测试手段、测点位置、测点数量对相关系数的影响,以及多参数时预测模型的最优自变量组合.结果表明:增加测点数量可提高无损指标与木材抗弯强度的相关系数;当自变量较多时,逐步回归法适合应用于确定最优自变量组合,同时避免自变量共线性问题;相较于一元线性模型,使用最优自变量组合确定的多元线性模型可使无损指标与抗弯强度的相关系数和校正决定系数分别提高20.54%和42.92%,表明多测点无损检测法可以有效提高木材抗弯强度预测的准确性.

关键词：古建木材无损检测抗弯强度逐步回归法多元模型

μ-and m-calpain expression and activity changes following diethylstilbestrol injection in the rat anterior pituitary

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Neural Regeneration Research 2011年第1期6卷 60-65页

作者： Weijiang Zhao Zhongfang Shi Fang Yuan Guilin Li Yazhuo Zhang zhongcheng wang Neuroscience Center Shantou University Medical College Shantou 51504 I Guangdong Province China Beijing Neurosurgical Institute Capital Medical University Beijing 100050 China

Little is known about changes in calpain activity in the pituitary gland. In the present study,μ- and m-calpain activity changes were detected in the rat anterior pituitary following intraperitoneal injection of diethylstilbestrol. Double-immunofluorescence labeling confirmed colocalization of μ- and m-calpain in prolactin-secreting cells （lactotrophs）. Western blot analysis revealed significantly increased expression of both calpains, which accompanied upregulated cytosol and membrane zymographic activities at 12 weeks following diethylstilbestrol injection, compared with rats injected with sunflower oil. Moreover, following estrogen injection, pituitary gland pathological damage gradually worsened with increasing time. Results demonstrated that estrogen regulated calpain expression and activity, and both calpains participated in the pathophysiological processes of the pituitary gland. Ubiquitous calpain expression could serve as an effective target for anti-estrogen drugs.

关键词： diethylstilbestrol ubiquitous calpain anterior pituitary prolactinoma Wistar rats