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Development and prospect of downhole monitoring and data transmission technology for separated zone water injection

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Petroleum Exploration and Development 2023年第1期50卷 191-201页

作者： LIU He ZHENG Lichen yu jiaqing MING Eryang YANG Qinghai JIA Deli CAO Gang PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China

This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in *** to the development stages,the principles,operation processes,adaptability and application status of traditional downhole data acquisition method,cable communications and testing technology,cable-controlled downhole parameter real-time monitoring communication method and downhole wireless communication technology are introduced in *** and challenges of existing technologies in downhole monitoring and data transmission technology are pointed *** to the production requirement,the future development direction of the downhole monitoring and data transmission technology for separated zone water injection is *** the large number of wells adopting cable measuring and adjustment technology,the key is to realize the digitalization of downhole *** the key monitoring wells,cable-controlled communication technology needs to be improved,and downhole monitoring and data transmission technology based on composite coiled tubing needs to be developed to make the operation more convenient and *** large-scale application in oil fields,downhole wireless communication technology should be developed to realize automation of measurement and *** line with ground mobile communication network,a digital communication network covering the control center,water distribution station and oil reservoir should be built quickly to provide technical support for the digitization of reservoir development.

关键词： separated zone water injection downhole monitoring data transmission cable communication vibration wave pressure wave flow wave

Automatic diagnosis of diabetic retinopathy using vision transformer based on wide-field optical coherence tomography angiography

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Journal of Innovative Optical Health Sciences 2024年第2期17卷 35-44页

作者： Zenan Zhou Huanhuan yu jiaqing Zhao Xiangning Wang Qiang Wu Cuixia Dai Shanghai Institute of Technology Shanghai P.R.China Shanghai Sixth People'sHospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai P.R.China

Diabetic retinopathy(DR)is one of the major causes of visual impairment in adults with *** coherence tomography angiography(OCTA)is nowadays widely used as the golden criterion for diagnosing ***,wide-field OCTA(WF-OCTA)provided more abundant information including that of the peripheral retinal degenerative changes and it can contribute in accurately diagnosing *** need for an automatic DR diagnostic system based on WF-OCTA pictures attracts more and more attention due to the large diabetic population and the prevalence of retinopathy *** this study,automatic diagnosis of DR using vision transformer was performed using WF-OCTA images(12 mm×12 mm single-scan)centered on the fovea as the ***-OCTA images were automatically classified into four classes:No DR,mild nonproliferative diabetic retinopathy(NPDR),moderate to severe NPDR,and proliferative diabetic retinopathy(PDR).The proposed method for detecting DR on the test set achieves accuracy of 99.55%,sensitivity of 99.49%,and specificity of 99.57%.The accuracy of the method for DR staging reaches up to 99.20%,which has been proven to be higher than that attained by classical convolutional neural network *** show that the automatic diagnosis of DR based on vision transformer and WF-OCTA pictures is more effective for detecting and staging DR.

关键词： Wide field optical coherence tomography angiography diabetic retinopathy vision transformer image classification

Development and prospect of separated zone oil production technology

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Petroleum Exploration and Development 2020年第5期47卷 1103-1116页

作者： LIU He ZHENG Lichen YANG Qinghai yu jiaqing yuE Qingfeng JIA Deli WANG Quanbin PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China Daqing Oilfield Production Engineering Research Institute Daqing 163453China

This article outlines the development of separated zone oil production in foreign countries,and details its development in *** to the development process,production needs,technical characteristics and adaptability of oilfields in China,the development of separate zone oil production technology is divided into four stages:flowing well zonal oil production,mechanical recovery and water blocking,hydraulically adjustable zonal oil production,and intelligent zonal *** principles,construction processes,adaptability,advantages and disadvantages of the technology are introduced in *** on the actual production situation of the oilfields in China at present,three development directions of the technology are ***,the real-time monitoring and adjustment level of separated zone oil production needs to be improved by developing downhole sensor technology and two-way communication technology between ground and downhole and enhancing full life cycle service capability and adaptability to horizontal ***,an integrated platform of zonal oil production and management should be built using a digital artificial lifting ***,integration of injection and production should be implemented through large-scale application of zonal oil production and zonal water injection to improve matching and adjustment level between the injection and production parameters,thus making the development adjustment from"lag control"to"real-time optimization"and improving the development effect.

关键词： separated zone oil production flowing well zonal oil production mechanical recovery and water plugging hydraulically adjustable zonal oil production intelligent zonal oil production prospect

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Doubly selective fading channel estimation in MIMO OFDM systems

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Science in China(Series F) 2005年第6期48卷 795-807页

作者： yu Xiaoyan WANG jiaqing YANG Luxi HE Zhenya Department of Radio Engineering Southeast University Nanjing 210096 China

High data transmission rates and high mobility give rise to time- and frequency-selectivity in wireless communication channels. This paper investigated time and frequency doubly selective channel estimation using pilot tones among Multi-Input Multi-Output （MIMO） orthogonal frequency division multiplexing （OFDM）. Firstly, a complex exponential basis expansion channel model （BECM） was introduced to represent doubly selective channel during an OFDM symbol period; then, based on BECM, an effective MIMO-OFDM doubly selective channel estimation method was presented; finally, the optimality in designing pilot tones parameters was done according to the minimization of channel estimation MSE, mainly including the number, the placement and the structure of pilot tones. Simulation results show that the proposed estimation method has good performance in doubly selective channel scenarios and confirms the theoretical analysis findings.

关键词： MIMO-OFDM doubly selective channels channel estimation basis expansion channel model.

当代中国社会环境下的传统文化变迁：一项社会学的考察

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复旦学报(社会科学版) 2022年第5期64卷 186-196页

作者：胡安宁余家庆复旦大学社会学系

传统文化在现代社会的嬗变是一个经典的社会科学研究议题。本文立足于现有关于中国传统文化的理论讨论，通过道德观(人与人)、家庭观(人与家)和政治观(人与国)三个方面对中国传统文化进行分析，强调了传统文化中“仁”、“孝”和“忠”... 详细信息

传统文化在现代社会的嬗变是一个经典的社会科学研究议题。本文立足于现有关于中国传统文化的理论讨论，通过道德观(人与人)、家庭观(人与家)和政治观(人与国)三个方面对中国传统文化进行分析，强调了传统文化中“仁”、“孝”和“忠”三个基本主题。围绕这三个主题，本文基于社会学关于中国社会变迁所积累的经验事实，论证了当代中国社会传统文化变迁的基本方向与形态：“仁”的观念从内外有别的差序交往结构逐渐转向内外平衡的宽半径合作；“孝”的观念从权威关系主导逐渐转向权威关系和亲情关系的有机统一；“忠”的观念从文化为中轴逐渐转向文化信赖与制度化评价并立的格局。

关键词：传统文化现代化社会学

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曲线曲面小波分解偏差估计

计算机辅助设计与图形学学报 2012年第8期24卷 984-988,996页

作者：俞佳庆赵罡北京航空航天大学机械工程及自动化学院北京100191 北京航空航天大学虚拟现实技术与系统国家重点实验室北京100191

针对曲线曲面小波变换后低分辨模型和原始高分辨模型之间的偏差问题,提出离散偏差模型方法来估计偏差.通过定义偏差曲线,并在此基础上提出离散偏差曲线法来估计高分辨曲线和低分辨曲线之间的偏差:给定弓高误差限,用等误差方法离散偏差曲... 详细信息

针对曲线曲面小波变换后低分辨模型和原始高分辨模型之间的偏差问题,提出离散偏差模型方法来估计偏差.通过定义偏差曲线,并在此基础上提出离散偏差曲线法来估计高分辨曲线和低分辨曲线之间的偏差:给定弓高误差限,用等误差方法离散偏差曲线,利用离散点估计偏差.同时,将该思想推广到曲面小波分解偏差估计上,定义了偏差曲面,并提出离散偏差曲面法来估计高分辨曲面和低分辨曲面之间的偏差.实验结果表明,文中算法既可以实现分解n次之后的低分辨模型的偏差估计,又可以通过减小离散误差提高估计精度.

关键词：小波变换偏差估计曲线曲面离散

PERFORMANCE EVALUATION OF LOW DENSITY PARITY CHECK CODES FOR DIGITAL RADIO MONDIALE (DRM) SYSTEM

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Journal of Electronics(China) 2006年第2期23卷 189-192页

作者： Wang jiaqing yu Xiaoyan Wu Lenan Department of Radio Engineering Southeast University Nanjing 210096 China

In Digital Radio Mondiale (DRM) system, achieving good audio quality becomes a challenge due to its limited band-width of 9 or 10kHz and the very bad fading channels. Therefore, DRM needs highly efficient channel coding schemes. This paper, proposes the schemes which use the Low-Density Parity-Check (LDPC) coded Bit-Interleaved Coded Modulation (BICM) schemes for the implementation of DRM systems. Simulation results show that the proposed system is more efficient than the Rate Compatible Punctured Con volutional (RCPC) coded DRM system on various broadcast channels, and may be recommended as a coding technology for Digital Amplitude Modulation Broadcasting (DAMB) systems of China.

关键词：低密度奇偶检测码 LDPC 隔行扫描 DRM 音频质量

共情护理结合SBAR沟通系统在妊娠糖尿病产妇中的应用效果

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妇儿健康导刊 2023年第18期2卷 137-139页

作者：余嘉卿郭羽张静中国医学科学院北京协和医院国际产科北京100005

目的探讨共情护理结合SBAR沟通系统在妊娠糖尿病产妇中的应用效果。方法选取北京协和医院2021年1月至2022年12月收治的60例妊娠糖尿病患者,按照随机数字表法分为观察组、对照组,每组各30例。对照组采用常规护理,观察组在常规护理基础上... 详细信息

目的探讨共情护理结合SBAR沟通系统在妊娠糖尿病产妇中的应用效果。方法选取北京协和医院2021年1月至2022年12月收治的60例妊娠糖尿病患者,按照随机数字表法分为观察组、对照组,每组各30例。对照组采用常规护理,观察组在常规护理基础上采用共情护理结合SBAR沟通系统,比较两组应用效果。结果干预后观察组焦虑、抑郁评分低于对照组(P<0.05);观察组遵医行为评分高于对照组(P<0.05)。结论共情护理结合SBAR沟通系统在妊娠糖尿病患者中的应用效果较好,可以改善心理状态,提升遵医行为。

关键词：共情护理 SBAR沟通系统妊娠糖尿病

分层注水井下监测与数据传输技术的发展及展望

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石油勘探与开发 2023年第1期50卷 174-182页

作者：刘合郑立臣俞佳庆明尔扬杨清海贾德利曹刚中国石油勘探开发研究院北京100083

概述了中国分层注水井下监测与数据传输技术的发展状况,按照发展阶段介绍了传统井下数据获取方法、电缆直读通讯与测调技术、预置电缆井下参数实时监测通讯技术以及井下无线通讯技术,详细介绍了技术原理、施工工艺、技术适应性和应用概... 详细信息

概述了中国分层注水井下监测与数据传输技术的发展状况,按照发展阶段介绍了传统井下数据获取方法、电缆直读通讯与测调技术、预置电缆井下参数实时监测通讯技术以及井下无线通讯技术,详细介绍了技术原理、施工工艺、技术适应性和应用概况,指出了现有井下监测与数据传输技术存在的问题及面临的挑战,最后根据生产需求,提出了分层注水井下监测与数据传输技术的发展方向。对于已规模应用的电缆高效测调井,着重实现井下堵塞器数字化;对于重点监测井,进一步完善预置电缆通讯技术,发展基于复合连续管的井下监测与数据传输技术,提高施工的便捷性和可靠性;对于规模生产应用,发展井下无线通讯技术,重点实现测调自动化,并结合地面移动通讯网络,加快构建覆盖控制中心、配水间和油藏的数字化通讯网络,为油藏开发数字化提供技术支撑。

关键词：分层注水井下监测数据传输电缆通讯振动波压力波流量波