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Risk assessment of oil and gas pipelines hot work based on AHP-FCE

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Petroleum 2023年第1期9卷 94-100页

作者： san he Huilan Xu Jianxiong Zhang Peiqiang Xue Southwest Petroleum University Chengdu610500China Sinopec Southwest Oil&Gas Company Chengdu610095China PetroChina Southwest Oil and Gas Field Company Shunan Gas Mine Luzhou64600China PetroChina Qinghai Oilfield Downhole Operation Company Haixi Mongolian and Tibetan Autonomous Prefecture816100QinghaiChina

A new quantitative risk assessment method for hot work is proposed based on the analytic hierarchy process(AHP)and fuzzy comprehensive evaluation(FCE).It can help pipeline companies realize the risk management of hot work and further ensure the safe operation of oil and gas *** one natural gas pipeline in China as an example,this paper evaluates the risk of a single hot work in the spring of one natural gas pipeline in a high consequence *** of all,the risk factors are determined with reference to the job safety analysis(JSA),and then experts were invited to fill out a questionnaire to collect their *** to the results of the questionnaire,AHP is used to calculate the weight coefficients of the evaluation indicators,and FCE is used to evaluate the risk level of hot *** calculation,the comprehensive risk score of hot work is *** belongs to a"general risk".This method can not only quantitatively evaluate the risk levels of hot work,but also reasonably sort the importance of various risk *** is helpful for the effective management of hot work and provides suggestions for implementing control measures.

关键词： Oil and gas pipelines Hot work Risk assessment Analytic hierarchy process(AHP) Fuzzy comprehensive evaluation(FCE)

A neutron diffraction investigation of high valent doped barium ferrite with wideband tunable microwave absorption

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Journal of Advanced Ceramics 2022年第2期11卷 263-272页

作者： Jun LI Yang HONG san he Weike LI Han BAI Yuanhua XIA Guangai SUN Zhongxiang ZHOU School of Physics Harbin Institute of TechnologyHarbin 150001China heilongjiang Provincial Key Laboratory of Plasma Physics and Application Technology Harbin Institute of TechnologyHarbin 150001China School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory for Neutron Physics of CAEP Institute of Nuclear Physics and ChemistryMianyang 621999China

The barium ferrite BaTi_(x)Fe_(12−x)O_(19)(x=0.2,0.4,0.6,0.8)(BFTO-x)ceramics doped by Ti4+were synthesized by a modified sol–gel *** crystal structure and magnetic structure of the samples were determined by neutron diffraction,and confirm that the BFTO-x ceramics were high quality single phase with sheet *** x increasing from 0.2 to 0.8,the saturation magnetization(M_(s))decreases gradually but the change trend of coercivity(H_(c))is complex under the synergy of the changed grain size and the magnetic crystal anisotropy *** on the high valence of Ti^(4+),double resonance peaks are obtained in the curves of the imaginary part of magnetic conductivity(μ′′)and the resonance peaks could move toward the low frequency with the increase of x,which facilitate the samples perform an excellent wideband modulation microwave absorption *** the x=0.2 sample,the maximum reflection loss(RL)can reach−44.9 dB at the thickness of only 1.8 mm,and the bandwidth could reach 5.28 GHz at 2 mm when RL is less than−10 *** the BFTO-x ceramics show excellent frequency modulation ability varying from 18(x=0.8)to 4 GHz(x=0.4),which covers 81%of the investigated frequency in microwave absorption *** work not only implements the tunable of electromagnetic parameters but also broadens the application of high-performance microwave absorption devices.

关键词： barium ferrite neutron diffraction microwave absorption

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S气田天然气压缩机组能效提升技术研究

石油石化节能与计量 2024年第1期14卷 21-25,31页

作者：兰海涛赵玥颖姚岸林邱海涛贺三青海油田钻采工艺研究院西南石油大学石油与天然气工程学院

S气田投产后进入中后期,天然气处理量偏低,天然气压缩机组进排气压力偏离设计工况,导致机组出现能耗高、效率低的现象。以S气田中的5号站、9号站和15号站三个区块为研究对象,分析运行与能效现状,提出四种提效节能方案:压缩机组开关机策... 详细信息

S气田投产后进入中后期,天然气处理量偏低,天然气压缩机组进排气压力偏离设计工况,导致机组出现能耗高、效率低的现象。以S气田中的5号站、9号站和15号站三个区块为研究对象,分析运行与能效现状,提出四种提效节能方案:压缩机组开关机策略;单双调节改造;高压变频改造;更换小排量压缩机组。通过HYSYS和Pipeline Studio软件模拟得到方案改造后结果。结果表明:改造后单台机组效率平均提升55.44%,均达到节能评价值,单台节能率最高为53.53%,整体节能率达29.77%,有效提升系统能效,减少能耗。

关键词：天然气压缩机组高压变频改造单双作用调节选择性运行

A regression approach for seismic first-break picking

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Petroleum Science 2024年第3期21卷 1584-1596页

作者： Huan Yuan san-Yi Yuan Jie Wu Wen-Jing sang Yu-he Zhao CNPC Key Laboratory of Geophysical Exploration China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration&Development—Northwest(NWGI) Key Laboratory of reservoir characterization of CNPCPetroChinaLanzhou 730020GansuChina

The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)***,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)*** address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target *** employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed *** from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and *** addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary *** picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large *** picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR *** subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed *** results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application.

关键词： First-break picking Low signal-to-noiseratio Regression BiLSTM Traveltime Geometry Noisy seismic data

Analytical computation of magnetic field in coil-dominated superconducting quadrupole magnets based on racetrack coils

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Nuclear Science and Techniques 2024年第4期35卷 119-135页

作者： Chuang Shen Ying-Shun Zhu Fu-san Chen China Spallation Neutron Source Institute of High Energy PhysicsChinese Academy of Sciences1 Zhongziyuan RoadDongguan 523000China Institute of High Energy Physics Chinese Academy of Sciences19B Yuquan RoadBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and ***,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications *** with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical *** this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are *** analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current ***,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 10^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed.

关键词： Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design

Quantifying muskmelon fruit attributes with A-TEP-based model and machine vision measurement

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Journal of Integrative Agriculture 2018年第6期17卷 1369-1379页

作者： CHANG Li-ying he san-peng LIU Qian XIANG Jia-lin HUANG Dan-feng School of Agriculture and Biology Shanghai Jiaotong University

In this study, we established a dynamic morphological model using the accumulated thermal effectiveness and photosynthetic active radiation （PAR）（A-TEP）, aiming to explore the relationship between muskmelon （Cucumis melo L.） fruit attributes and environmental factors. Muskmelon surface color was described by parameters of red, green, blue, hue, saturation and brightness （HSI）. Three characteristic parameters, gray level co-occurrence matrix （GLCM）, angular second moment （ASM）, entropy, contrast, and the coverage rate were used to describe the process of muskmelon fruit netting formation. ASM was not significant difference during muskmelon fruit growth. The number and deep of netting stripes gradually increased with fruit growth. Coverage rate increased rapidly for 15-30 d after pollination. The vertical and horizontal diameters of muskmelon fruit were followed a logistic curve. And root mean squared errors （RMSE） between the simulated and measured vertical and horizontal diameters were 3.527 and 4.696 mm, respectively. RMSE of red, green, blue, saturation and brightness were 0.999, 2.690, 2.992, 0.033 and 5.51, respectively, and the RMSE for entropy, contrast and coverage rates were 0.077, 0.063 and 0.015, respectively, indicating a well consistent between measured and simulated values.

关键词： machine vision technology fruit attributes A-TEP skin netting coverage rate

Modeling Study of Fruit Morphological Formation in Melon

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Agricultural Sciences in China 2011年第5期10卷 714-720页

作者： CHANG Li-ying NIU Qing-liang MIAO Yu-bin he san-peng CUI Chong HUANG Dan-feng School of Agriculture and Biology Shanghai Jiaotong University Shanghai 200240 P.R.China

Modeling of fruit morphological formation in melon is important for realizing virtual and digital plant *** objective of this study was to characterize the changes in patterns of fruit growth characters during plant *** cultivar experiments,a high-resolution wireless vision sensor network has been developed to realize non-contact automatic uninterrupted measurement of the fruit shape micro-change （fruit size,color,and net）.Results showed that the fruit swelling process （vertical and horizontal diameters） exhibited a slow-rapid-slow pattern,which could be well described with a logistic curve against growing degree days （GDD）;fruit color changes based on the RGB values could be represented by quadratic relationship to cumulative GDD;the fruit net changes over growth progress could be partitioned into three phases according to the time *** first phase was from 1 to 30 days after pollination （DAP）,in which the vertical stripe appeared at fruit middle part and the horizontal stripe at fruit petiole and hilum part as well;the second phase was from 30 to 40 DAP,the horizontal stripe occurred at fruit middle part and the net was formed;the third phase was the process started from 40 DAP,the netted breadth and thickness were gradually *** model was validated with the independent data from the experiment,and the mean RMSE （root mean square error） of fruit were 0.36 and 0.28 cm for vertical and horizontal diameters,11.9 for fruit color,and 0.45 cm for stripe length and diameter at varied GDD,*** work is beneficial to a reliable foundation for study the relationship between morphological formation and physiological change of the melon fruit internally and then realize the intelligent precision management to improve the yield and quality of greenhouse melon production.

关键词： melon (Cucumis melo L.) morphological formation model fruit diameter fruit color fruit net growing degreedays (GDD)

A seismic elastic moduli module for the measurements of low-frequency wave dispersion and attenuation of fluid-saturated rocks under different pressures

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Petroleum Science 2024年第1期21卷 162-181页

作者： Yan-Xiao he Shang-Xu Wang Gen-Yang Tang Chao Sun Hong-Bing Li san-Yi Yuan Xian Wei Li-Deng Gan Xiao-Feng Dai Qiang Ge Peng-Peng Wei Hui-Qing Zhang National Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationCollege of GeophysicsChina University of Petroleum(Beijing)Beijing102249China School of Resources and Geosciences China University of Mining and TechnologyXuzhou221116JiangsuChina Research Institute of Petroleum Exploration and Development CNPCBeijing100083China Beijing Vocational College of Labour and Social Security Beijing100029China PetroChina Dagang Oilfield Exploration and Development Research Institute CNPCTianjin300280China

Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and time-lapse seismic surveillance of both conventional and unconventional reservoir and overburden performances.A Seismic Elastic Moduli Module has been developed,based on the forced-oscillations method,to experimentally investigate the frequency dependence of Young's modulus and Poisson's ratio,as well as the inferred attenuation,of cylindrical samples under different confining pressure *** with three standard samples showed that the measured elastic moduli were consistent with the published data,indicating that the new apparatus can operate reliably over a wide frequency range of f∈[1-2000,10^(6)]*** Young's modulus and Poisson's ratio of the shale and the tight sandstone samples were measured under axial stress oscillations to assess the frequency-and pressure-dependent *** dry condition,both samples appear to be nearly frequency independent,with weak pressure dependence for the shale and significant pressure dependence for the *** particular,it was found that the tight sandstone with complex pore microstructure exhibited apparent dispersion and attenuation under brine or glycerin saturation conditions,the levels of which were strongly influenced by the increased effective *** addition,the measured Young's moduli results were compared with the theoretical predictions from a scaled poroelastic model with a reasonably good agreement,revealing that the combined fluid flow mechanisms at both mesoscopic and microscopic scales possibly responsible for the measured dispersion.

关键词： Low-frequency measurements Dispersion and attenuation Rock physics Fluid flow

Ion and electron motions in the outer electron diffusion region of collisionless magnetic reconnection

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Earth and Planetary Physics 2024年第3期8卷 472-478页

作者： Cong Chang QuanMing Lu san Lu Kai Huang RongSheng Wang Deep Space Exploration Laboratory School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences(CAS)Center for Excellence in Comparative Planetology CAS Key Laboratory of Geospace EnvironmentHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China

Two-dimensional particle-in-cell simulations are performed to study the coupling between ion and electron motions in collisionless magnetic *** electron diffusion region(EDR),where the electron motions are demagnetized,is found to have a two-layer structure:an inner EDR near the reconnection site and an outer EDR that is elongated to nearly 10 ion inertial lengths in the outflow *** the inner EDR,the speed of the electron outflow increases when the electrons move away from the X *** the outer EDR,the speed of the electron outflow first increases and then decreases until the electrons reach the boundary of the outer *** the boundary of the outer EDR,the magnetic field piles up and forms a depolarization *** the perspective of the fluid,a force analysis on the formation of electron and ion outflows has also been *** the X line,the electrons are accelerated by the reconnection electric field in the out-of-plane *** the electrons move away from the X line,we find that the Lorentz force converts the direction of the accelerated electrons to the x direction,forming an electron *** electric field forces and electron gradient forces tend to drag the electron *** acceleration along the x direction is caused by the Lorentz force,whereas the pressure gradient force tends to decelerate the ion *** these two terms are important,their effects on ions are almost *** Hall electric field force does positive work on ions and is not *** ions are continuously accelerated,and the ion and electron outflow velocities are almost the same near the depolarization front.

关键词： collisionless magnetic reconnection electron diffusion region force analysis particle-in-cell simulation