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基于合成场强仪的输电工程地面合成电场研究

自动化仪表 2024年第1期45卷 91-95页

作者：张小庆洪倩丰佳胡笳林旗力中国电力工程顾问集团华东电力设计院有限公司上海200001 国网经济技术研究院有限公司北京102209 国网浙江省电力有限公司浙江杭州310007 浙江大学资源与环境学院浙江杭州310058

高压直流(DC)输电线路交叉跨越是我国特高压(UHV)技术发展中出现的问题。由于两回DC线路相互影响,交叉跨越区域内合成电场呈复杂的三维分布,UHV DC输电工程地面合成电场计算较为困难。选取典型±800 kV UHV DC输电工程进行地面合成电场... 详细信息

高压直流(DC)输电线路交叉跨越是我国特高压(UHV)技术发展中出现的问题。由于两回DC线路相互影响,交叉跨越区域内合成电场呈复杂的三维分布,UHV DC输电工程地面合成电场计算较为困难。选取典型±800 kV UHV DC输电工程进行地面合成电场的实测研究。参照GB 39220—2020,采用HDEM-01合成场强仪进行野外现场实测。测量参数为有效期内的场磨传感器上积聚的电荷量。测量结果与运行初期实测数据的对比结果表明:±800 kV换流站周边运行初期合成电场强度略低于后期,且整体水平较低;沿线电磁环境敏感目标运行初期、后期的实测数据中,74%的数值小于5 kV/m。通过此次研究,明确了UHV DC输电工程合成电场不同时期的特性。该研究有助于推进UHV DC输电工程的快速建成,并提高其运行安全性,从而推动电力工程建设的发展。

关键词：直流输电工程地面合成电场特高压电网分布特征电磁环境本底值换流站

调度操作票自动校验的CNN-BiLSTM方法

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核电子学与探测技术 2024年第2期44卷 316-322页

作者：吴奇珂程培军钱韦廷姜浩宇胡佳广东电网有限责任公司广州供电局电力调度控制中心广州510620

基于人工经验的核电厂变电站电力调度操作票校验方法具有主观性强、校验效率低、可靠性不高等问题,为解决上述问题,提出了一种基于卷积神经网络(CNN)和双向长短时记忆网络(BiLSTM)的操作票自动校验方法。该方法在对操作票文本进行向量... 详细信息

基于人工经验的核电厂变电站电力调度操作票校验方法具有主观性强、校验效率低、可靠性不高等问题,为解决上述问题,提出了一种基于卷积神经网络(CNN)和双向长短时记忆网络(BiLSTM)的操作票自动校验方法。该方法在对操作票文本进行向量化的基础上,利用CNN-BiLTSM模型实现操作票文本的深度信息挖掘和校验的自动化。实验结果表明,相比单一模型,CNN-BiLSTM模型的校验精度更高,校验评估综合指标可达95.67%,具有一定的优势。

关键词：卷积神经网络操作票自动校验双向长短时记忆网络

High-temperature corrosion of phosphate completion fluid and corrosion inhibition method by membrane transformation

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Petroleum Exploration and Development 2023年第6期50卷 1497-1508页

作者： jia hu HE Wei NIU Chengcheng National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China

By analyzing the corrosion of phosphate completion fluid on the P110 steel at 170 °C, the high-temperature corrosion mechanism of phosphate completion fluid was revealed, and a corrosion inhibition method by membrane transformation was proposed and an efficient membrane-forming agent was selected. Scanning electron microscope (SEM) images, X-ray energy spectrum and X-ray diffraction results were used to characterize the microscopic morphology, elemental composition and phase composition of the precipitation membrane on the surface of the test piece. The effect and mechanism of corrosion inhibition by membrane transformation were clarified. The phosphate completion fluid eroded the test piece by high-temperature water vapor and its hydrolyzed products to form a membrane of iron phosphate corrosion product. By changing the corrosion reaction path, the Zn2+ membrane-forming agent could generate KZnPO4 precipitation membrane with high temperature resistance, uniform thickness and tight crystal packing on the surface of the test piece, which could inhibit the corrosion of the test piece, with efficiency up to 69.63%. The Cu2+ membrane-forming agent electrochemically reacted with Fe to precipitate trace elemental Cu on the surface of the test piece, thus forming a protective membrane, which could inhibit metal corrosion, with efficiency up to 96.64%, but the wear resistance was poor. After combining 0.05% Cu2+ and 0.25% Zn2+, a composite protective membrane of KZnPO4 crystal and elemental Cu was formed on the surface of the test piece. The corrosion inhibition efficiency reached 93.03%, which ensured the high corrosion inhibition efficiency and generated a precipitation membrane resistant to temperature and wear.

关键词： phosphate completion fluid corrosion mechanism membrane transformation corrosion inhibition mechanism

Effect of reservoir heterogeneity on air injection performance in a light oil reservoir

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Petroleum 2018年第1期4卷 15-24页

作者： hu jia State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China

Air injection is a good option to development light oil *** well-known that,reservoir heterogeneity has great effect for various EOR *** also applies to air ***,oil recovery mechanisms and physical processes for air injection in heterogeneous reservoir with dip angle are still not well *** reported setting of reservoir heterogeneous for physical model or simulation model of air injection only simply uses different-layer permeability of porous *** practice,reservoir heterogeneity follows the principle of *** much of contrast in permeability actually challenges the air injection in light oil reservoir?This should be investigated by using layered porous medial settings of the classical Dykstra-Parsons ***,there has been no work addressing this issue for air injection in light oil *** this paper,Reservoir heterogeneity is quantified based on the use of different reservoir permeability distribution according to classical Dykstra-Parsons coefficients *** aim of this work is to investigate the effect of reservoir heterogeneity on physical process and production performance of air injection in light oil reservoir through numerical reservoir simulation *** basic model is calibrated based on previous *** eleven pseudo compounders are included in this model and ten complexity of reactions are proposed to achieve the reaction *** show that oil recovery factor is decreased with the increasing of reservoir heterogeneity both for air and N2 injection from updip location,which is against the working behavior of air injection from updip *** heterogeneity sometimes can act as positive effect to improve sweep efficiency as well as enhance production performance for air *** O2 content air injection can benefit oil recovery factor,also lead to early O2 breakthrough in heterogeneous ***-type does not show great effect on producti

关键词： Air injection Light oil Heterogeneity Dykstra-parsons coefficients Enhanced oil recovery Recovery mechanism

冠心病患者彩超下颈动脉弹性指标及心外膜脂肪层厚度与病情严重程度的关系分析

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当代医学 2024年第7期30卷 54-57页

作者：肖娟袁新春胡佳赣州市中医院功能科江西赣州341000 南昌大学第一附属医院超声医学科江西赣州330006

目的分析冠心病(CHD)患者彩超下颈动脉弹性指标、心外膜脂肪层厚度(EFT)与病情严重程度的关系。方法选取2019年1月至2022年2月赣州市中医院收治的120例CHD患者作为实验组,根据患者病情严重程度分为A组(轻度,n=30)、B组(中度,n=48)、C组... 详细信息

目的分析冠心病(CHD)患者彩超下颈动脉弹性指标、心外膜脂肪层厚度(EFT)与病情严重程度的关系。方法选取2019年1月至2022年2月赣州市中医院收治的120例CHD患者作为实验组,根据患者病情严重程度分为A组(轻度,n=30)、B组(中度,n=48)、C组(重度,n=42),另选取同期接受健康检查的50名健康者作为对照组。采用彩超检查患者颈动脉弹性指标、EFT并探讨两者与病情严重程度的关系。结果实验组内中膜厚度(IMT)、血管僵硬度(β)、弹性模量(Ep)均高于对照组,脉搏波传导速度(PWV-β)快于对照组,顺应性(AC)低于对照组,差异有统计学意义(P1,P<0.05)。结论IMT、β、Ep、AC、EFT升高,PWV-β加快,AC降低是影响CHD患者病情严重程度的独立危险因素,颈动脉弹性指标、EFT可作为评估CHD患者疾病严重程度的重要指标,值得临床推广应用。

关键词：冠心病颈动脉弹性心外膜脂肪层厚度

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基于改进SRC的局部遮挡人脸识别方法

太原科技大学学报 2024年第1期45卷 7-12页

作者：胡思佳赵志诚太原科技大学电子与信息工程学院太原030024

针对现实场景中人脸存在较为随机的局部遮挡的情形,创建了多种遮挡类型并存的过完备字典,并提出改进的稀疏表示分类方法。此算法在稀疏表示分类(Sparse Representation Based Classification,SRC)的基础上引入噪声补偿,通过对测试图像... 详细信息

针对现实场景中人脸存在较为随机的局部遮挡的情形,创建了多种遮挡类型并存的过完备字典,并提出改进的稀疏表示分类方法。此算法在稀疏表示分类(Sparse Representation Based Classification,SRC)的基础上引入噪声补偿,通过对测试图像与去噪图像间噪声差的调节来控制重构图像的生成,进而实现对重构图像与测试图像间残差的控制,以达到准确分类识别的效果。实验结果表明,改进后的算法稳定性好、识别率高,对于局部遮挡图像的识别有较好的鲁棒性。

关键词：局部遮挡稀疏表示噪声补偿人脸识别

Effects of physical parameter range on dimensionless variable sensitivity in water flooding reservoirs

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Acta Mechanica Sinica 2006年第5期22卷 385-391页

作者： Yu hu Bai jia Chun Li Ji Fu Zhou Division of Engineering Sciences Institute of MechanicsChinese Academy of Sciences Beijing 100080 China

The similarity criterion for water flooding reservoir flows is concerned with in the present paper. When finding out all the dimensionless variables governing this kind of flow, their physical meanings are subsequently elucidated. Then, a numerical approach of sensitivity analysis is adopted to quantify their corresponding dominance degree among the similarity parameters. In this way, we may finally identify major scaling law in different parameter range and demonstrate the respective effects of viscosity, permeability and injection rate.

关键词： Physical parameter range Dimensionless variable Sensitivity analysis Water flooding reservoir Two-phase flow in porous media

The Kinematic Analyses of the 3-DOF Parallel Machine Tools

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International Journal of Automation and computing 2011年第1期8卷 107-111页

作者： Ming hu jia-Shun Shi School of Mechanical Engineering and Automation Northeastern University Shenyang 110004 PRC

A 3-degree-of-freedom （3-DOF） parallel machine tool based on a tripod mechanism is developed and studied. The kinematics analysis is performed, the workspace is derived, and an analysis on the number of conditions of the Jacobian matrix and manipulability is carried out. A method for error analysis and manipulability is introduced. Hence, the manipulability analysis of the parallel machine tool is accomplished.

关键词： Parallel machine tool kinematics Jacobian matrix error workspace.

Quantitative tracing of bioprobes by simultaneously monitoring radiative and nonradiative relaxations

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创新光学健康科学杂志(英文) 2023年第4期16卷 40-47页

作者： Hongjiang Chen Xiaoyu Tang Guangshuai Nie Zhen Wang jia hu Jun hu huan Qin Department of Orthopaedics The First Affiliated Hospital of Shantou University Medical College Shantou 515041Guangdong ProvinceP.R.China MOE Key Laboratory of Laser Life Science&Institute of Laser Life Science College of Biophotonics South China Normal University Guangzhou 510631P.R.China Guangdong Provincial Key Laboratory of Laser Life Science College of Biophotonics South China Normal University Guangzhou 510631P.R.China Guangzhou Key Lab of Spectral Analysis and Functional Probes College of Biophotonics South China Normal University Guangzhou 510631P.R.China

Bioprobe based on fluorescence is widely used in biological and medical research due to its high sensitivity and ***,its quantification in vivo is complicated and often compromised by the interaction between the fluorophore with the environmental factors,as well as the optical scattering and absorption by the tissue.A high florescence quantum yield and minimal interference by the environment are key requirements for designing an effective bioprobe,and the prerequisitions severely limit the available *** propose that a comprehensive evaluation of potential bioprobe can be achieved by simultaneously measuring both radiative and nonradiative transitions,the two fundamental and complementary pathways for the energy *** approach will not only improve the accuracy of the quantification by catching the information from a broader spectrum of the energy,but also provide additional information of the probe environment that often impacts the balance between the two forms of the energy *** work first analyzes the underlying mechanism of the *** practical feasibility is then tested by means of simultaneous measurements of photoacoustic signal for the non-radiative and fluorescence for the radiative energy processes,*** is demonstrated that the systematic evaluation of the probe energy de-excitation results in an improved quantitative tracing of a bioprobe in complex environment.

关键词： Bioprobe fluorescence photoacoustic