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Optimization of refracturing timing for horizontal wells in tight oil reservoirs: A case study of Cretaceous Qingshankou Formation, Songliao Basin, NE China

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Petroleum Exploration and Development 2019年第1期46卷 153-162页

作者： GUO Jianchun TAO Liang zeng fanhui State Key Laboratory of Oil & Gas Reservoir Geology and Exploitation in Southwest Petroleum University

Tight oil reservoirs in Songliao Basin were taken as subjects and a novel idealized refracturing well concept was proposed by considering the special parameters of volume fracturing horizontal wells, the refracturing potential of candidate wells were graded and prioritized, and a production prediction model of refracturing considering the stress sensitivity was established using numerical simulation method to sort out the optimal refracturing method and timing. The simulations show that: with the same perforation clusters, the order of fracturing technologies with contribution to productivity from big to small is refracturing between existent fractured sections, orientation diversion inside fractures, extended refracturing, refracturing of existent fractures; and the later the refracturing timing, the shorter the effective time. Based on this, the prediction model of breakdown pressure considering the variation of formation pressure was used to find out the variation pattern of breakdown pressure of different positions at different production time. Through the classification of the breakdown pressure, the times of temporary plugging and diverting and the amount of temporary plugging agent were determined under the optimal refracturing timing. Daily oil production per well increased from 2.3 t/d to 16.5 t/d in the field test. The research results provide important reference for refracturing optimization design of similar tight oil reservoirs.

关键词： Songliao Basin tight oil reservoirs refracturing volume fracturing breakdown pressure temporary plugging and diverting

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基于因素空间理论的扫类连环多分类算法

辽宁工程技术大学学报（自然科学版） 2024年第1期43卷 111-118页

作者：曾繁慧王莹汪培庄孙慧辽宁工程技术大学理学院辽宁阜新123000 辽宁工程技术大学智能工程与数学研究院辽宁阜新123000

为解决多分类问题,基于因素空间理论中因素显隐的思想,在扫类连环分类算法基础上,定义类别的合并,提出因素显隐的合并扫类连环分类方法,给出算法步骤,并用数值算例进行分析;定义类别的两两组合,提出因素显隐的两两扫类连环分类方法,给... 详细信息

为解决多分类问题,基于因素空间理论中因素显隐的思想,在扫类连环分类算法基础上,定义类别的合并,提出因素显隐的合并扫类连环分类方法,给出算法步骤,并用数值算例进行分析;定义类别的两两组合,提出因素显隐的两两扫类连环分类方法,给出算法步骤,并用数值算例进行分析。提出采用因素显隐的差额绝对值方法解决两个算法执行过程中出现的决策类别分不开的问题;对UCI数据集中3个实例与支持向量机作了算法对比分析,研究结果表明:提出的合并扫类连环分类方法、两两扫类连环分类方法实现了因素显隐,分类算法的精确度优于支持向量机。多分类学习的因素显隐研究结论拓展了因素空间的理论及应用研究。

关键词：因素空间因素显隐扫类连环分类算法合并扫类连环分类算法两两扫类连环分类算法差额绝对值法

Numerical simulation of 23 June 2016 Yancheng City EF4 tornadic supercell and analysis of lightning activity

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Science China Earth Sciences 2017年第12期60卷 2204-2213页

作者： GUO FengXia LI Yang HUANG ZhaoChu WANG ManFei zeng fanhui LIAN ChunHao MU YiJun key laboratory of meteorological disaster ministry of education(klme)joint international research laboratory of climate and environment change(ilcec)collaborative innovation center on forecast and evaluation of meteorological disaster(cic-femd)key laboratory for aerosol-cloud-precipitation of china meteorological administrationnanjing university of information science&technologyNanjing 210044China

Based on the Weather Research Forecasting(WRF) model that features charging and discharging parameterization,relationships between tornado, hail and lightning were investigated for a tornado-producing(EF4 intensity) supercell thunderstorm over Yancheng City in Jiangsu Province, China, on 23 June 2016. Based on a sounding at 0800, there was a low lifting condensation level, substantial convective available potential energy(CAPE), and strong vertical wind shear near Yancheng City, which promote supercell development. At 1400, observations revealed that hail production and a dramatic increase of positive cloud-to-ground flash rates occurred simultaneously, maximizing five minutes later. The tornado occurred 30 min after the hail production. The time of minimum positive cloud-to-ground flash rates was 15 min later. The simulation indicated that the tornadic supercell moved eastward and that positive cloud-to-ground flash rates increased dramatically at 1400, the same as observed, but their maximum was 5 min later than observed. The simulated updraft volume peaked at 1425 and the simulated downdraft volume maximized5 min later, when the mesocyclone formed. Simulated reflectivities showed no hook echo and horizontal winds for different height at mid-low levels had a different cyclonic shear at 1430, favorable to mesocyclone formation. Based on the simulated results,the region of positively charged graupel ascended resulting from the region of high liquid water content was lifted by the strong updraft, forming a mid-level strong positive charge region. A lower negative charge region formed by the inductive charging mechanism of collisions between graupel and droplets at the bottom of the cloud, conducive to positive cloud-to-ground flashes.

关键词： Tornado Supercell WRF Hail Positive cloud-to-ground flashes

基于组网多普勒雷达径向速度场的福建近海台风中心定位研究

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热带气象学报 2024年第2期40卷 189-197页

作者：苏源倪悦曾凡辉张深寿龙岩市气象局福建龙岩364000

本文探讨了一种基于组网多普勒雷达径向速度零速度线(区)对福建近海台风中心定位的方法,该方法利用了台风中心位于雷达径向速度产品中零速度线(区)上的特征,理论上可以将两部(或以上)多普勒雷达零速度线(区)的重合点(或区域)认定为台风... 详细信息

本文探讨了一种基于组网多普勒雷达径向速度零速度线(区)对福建近海台风中心定位的方法,该方法利用了台风中心位于雷达径向速度产品中零速度线(区)上的特征,理论上可以将两部(或以上)多普勒雷达零速度线(区)的重合点(或区域)认定为台风中心,并利用空间密度聚类法和线性回归分析对台风零速度线(区)弯曲、不连续以及重合点不唯一等情况做进一步中心定位判定。研究发现,该方法时空分辨率高、定位精准,可以对发展形态不规则、速度模糊、临近登陆或登陆后的台风实现定位,对台风实时业务定位和路径预报等具有一定的参考价值,同时具有简单易行、适用范围广的优势。

关键词：台风中心定位多普勒雷达组网径向速度零速度线

PD1/PD-L1、中性粒细胞弹性蛋白酶、赖氨酰氧化酶在膀胱癌中的表达及其与膀胱癌预后的关系

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江西医药 2024年第3期59卷 244-248页

作者：熊星贾灵华包佑根吴萌曾繁辉黄余江西省人民医院南昌医学院第一附属医院泌尿外科南昌330000

目的探讨膀胱癌组织中程序性细胞死亡受体1(PD1)、程序性细胞死亡配体1(PD-L1)、中性粒细胞弹性蛋白酶(NE)、赖氨酰氧化酶(LOX)的表达水平及其表达差异与膀胱癌患者临床病理特征和预后的关系。方法选取2018年1月至2020年12月江西省人民... 详细信息

目的探讨膀胱癌组织中程序性细胞死亡受体1(PD1)、程序性细胞死亡配体1(PD-L1)、中性粒细胞弹性蛋白酶(NE)、赖氨酰氧化酶(LOX)的表达水平及其表达差异与膀胱癌患者临床病理特征和预后的关系。方法选取2018年1月至2020年12月江西省人民医院收治的56例膀胱癌患者的癌组织作为研究对象,并记录患者的复发和死亡情况进行分析研究。采用免疫组织化学染色法检测PD1、PD-L1、NE、LOX的表达情况,分析PD1、PD-L1、NE、LOX与患者的病理特征和预后的关系。结果免疫组化结果显示PD1在肿瘤相关免疫细胞中存在表达(46/56);TNM分期T2-T3期、高级别肿瘤和出现淋巴结转移的患者PD1和PDL-1的表达阳性率均明显升高,差异有统计学意义(P<0.05)。NE与PD1、PDL-1的表达呈正相关(P<0.05);LOX与PD-L1、PDL-1的表达呈正相关(P<0.05)。PD1阳性表达患者3年无进展生存率为58.70%(27/46),PD-L1阳性表达患者3年无进展生存率为43.48%(10/23),不同PD1、PD-L1表达患者的3年无进展生存率比较差异有统计学意义(P<0.05)。结论膀胱癌组织中PD1、PD-L1表达增加可作为膀胱癌患者潜在的预后预测指标,有助于筛选术后复发的高危患者,并为膀胱癌的免疫学治疗提供新靶点。

关键词：膀胱癌程序性细胞死亡受体1 程序性细胞死亡配体1 肿瘤相关中性粒细胞因子

维普期刊数据库博看期刊

电缆谐振试验中杂散电容对二阶滤波器衰减特性的影响

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电工技术 2024年第5期 189-191,196页

作者：张玲俐曾凡辉张斌刘明陈震宇张炳生国网江苏省泰州市供电公司江苏泰州225300 扬州市鑫源电气股份有限公司江苏扬州225264

电缆谐振试验需测量局部放电,为了减小谐振电抗器本体局放的干扰,常在电抗器后端添加二阶滤波器。试验中,向空载的试验设备本体施加80%额定电压,测量经过滤波后的局部放电为3 pC,不能满足小于1 pC的要求。通过仿真计算可知,衰减度主要... 详细信息

电缆谐振试验需测量局部放电,为了减小谐振电抗器本体局放的干扰,常在电抗器后端添加二阶滤波器。试验中,向空载的试验设备本体施加80%额定电压,测量经过滤波后的局部放电为3 pC,不能满足小于1 pC的要求。通过仿真计算可知,衰减度主要受滤波器尾端与分压器之间的杂散电容的影响,该杂散电容值越小,滤波器的滤波效果就越好,且随着放电频率(20~300 kHz)的增大,衰减度先逐渐增大后逐渐减小,最后逐步上升并趋于稳定。针对上述结果,通过改变现场滤波器和分压器的布局改变其之间的杂散电容:当滤波器与分压器呈直角排列时,其间的杂散电容为50.9 pF,电抗器的局放为3 pC;而当滤波器和分压器呈直线排布时,其间的杂散电容为36.5 pF,电抗器的局放减小为0.8 pC,满足小于1 pC的要求,该结果与仿真分析结论基本一致。

关键词：局部放电滤波器杂散电容衰减特性

Cluster analysis reveals a homogeneous subgroup of PCOS women with metabolic disturbance associated with adverse reproductive outcomes

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Chinese Medical Journal 2024年第5期137卷 604-612页

作者： Hanxiao Chen Rujun zeng Xun zeng Lang Qin The Reproductive Medical Center Department of Obstetrics and GynecologyWest China Second University HospitalSichuan UniversityChengduSichuan 610041China Key Laboratory of Birth Defects and Related of Women and Children of Ministry of Education West China Second University HospitalSichuan UniversityChengduSichuan 610041China

Background:Polycystic ovarian syndrome(PCOS)is a heterogeneous and complex reproductive endocrinological disease that could lead to infertility.There were many attempts to classify PCOS but it remains unclear whether there is a specific subgroup of PCOS that is associated with the best or worst reproductive outcomes of assisted reproductive techniques(ART).Methods:Infertile PCOS patients who underwent their first cycle of in vitro fertilization(IVF)in West China Second University Hospital,Sichuan University from January 2019 to December 2021 were included.Basic clinical and laboratory information of each individual were extracted.Unsupervised cluster analysis was performed.Controlled ovarian stimulation parameters and reproductive outcomes were collected and compared between the different clusters of PCOS.Results:Our analysis clustered women with PCOS into"reproductive","metabolic",and"balanced"clusters based on nine traits.Reproductive group was characterized by high levels of testosterone(T),sex hormone-binding globulin(SHBG),follicular stimulation hormone(FSH),luteinizing hormone(LH),and anti-Müllerian hormone(AMH).Metabolic group was characterized by high levels of body mass index(BMI),fasting insulin,and fasting glucose.Balanced group was characterized by low levels of the aforementioned reproductive and metabolic parameters,except for SHBG.Compared with PCOS patients in reproductive and balanced clusters,those in metabolic cluster had lower rates of good quality day 3 embryo and blastocyst formation.Moreover,PCOS patients in the reproductive cluster had greater fresh embryo transfer(ET)cancelation rate and clinical pregnancy rate after fresh ET than metabolic cluster(odds ratio[OR]=3.37,95%confidence interval[CI]:1.77-6.44,and OR=6.19,95%CI:1.58-24.24,respectively).And compared with PCOS of metabolic cluster,PCOS of balanced cluster also had higher chance for fresh ET cancelation(OR=2.83,95%CI:1.26-6.35).Conclusion:Our study suggested that PCOS patients in metabolic cluster may be associated with adverse re

关键词： Polycystic ovarian syndrome Assisted reproductive techniques Clustering analysis Metabolic disturbance Clinical pregnancy

Comparative Study on Different Methods for Prediction of Thermal Insulation Performance of Thermal Barrier Coating Used on Turbine Blades

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Journal of Thermal Science 2024年第1期33卷 172-189页

作者： ZHANG Zhixin zeng Wu ZHANG Xiaodong zeng Yuntao Advanced Gas Turbine Laboratory Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Advanced Energy and Power Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Innovation Academy for Light-duty Gas Turbine Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

As turbine inlet temperature gets higher and higher,thermal barrier coating(TBC) is more and more widely used in turbine blades.For turbine blades with TBC,it is of great significance to evaluate the temperature distribution of its substrate metal quickly and accurately,especially during the design stage.With different degrees of simplification such as whether to consider the change of the geometric size of the fluid domain by TBC and whether to consider the planar heat conduction in TBC,three different methods used in conjugate heat transfer(CHT) simulation to model the TBC of the turbine blades have been developed and widely used by researchers.However,little research has been conducted to investigate the influence of the three methods on the temperature distribution of turbine blade.To fill this gap,three geometric models were designed.They are a solid conduction model with a substrate metal layer and a TBC layer,a transonic turbine vane with internal cooling and TBC,and a plate cylindrical film hole cooling model with TBC.Different methods were used in these geometric models and their differences were carefully analyzed and discussed.The result shows that for the conduction model used in this paper,with the same TBC surface temperature distribution,the difference between the three methods is very small and can be ignored.For a transonic turbine vane with internal cooling,regarding the local maximum temperature of the substrate-TBC interface,the largest difference between the method in which TBC is considered as a thermal resistance or a virtual layer of cells and the method in which three-dimensional heat conduction equation of TBC is solved occurs at the trailing edge.The difference near the leading edge is below 2K.When employed to the film cooling model,the difference of the laterally averaged temperature of the substrate-TBC interface can be 8 K which is mainly due to the change of the length to diameter ratio of the film cooling hole by TBC.If the substrate thickness is reduced by the thickness of TBC wh

关键词： turbine blade thermal barrier coating conjugate heat transfer film cooling hole

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定向井压裂射孔方位优化及应用研究

西南石油大学学报（自然科学版） 2023年第1期45卷 117-126页

作者：王尔钧马磊曹峰冯明曾凡辉中海石油(中国)有限公司湛江分公司广东湛江524057 油气藏地质及开发工程国家重点实验室·西南石油大学四川成都610500

低渗储层采用定向井水力压裂是油气田增储上产和降本增效的重要措施和手段。射孔是压裂前打开储层的首要工序,射孔质量好坏直接影响定向井产能的发挥程度。为了降低储层起裂压力、减少砂堵风险,需要进行定向井压裂射孔方位优化。考虑原... 详细信息

低渗储层采用定向井水力压裂是油气田增储上产和降本增效的重要措施和手段。射孔是压裂前打开储层的首要工序,射孔质量好坏直接影响定向井产能的发挥程度。为了降低储层起裂压力、减少砂堵风险,需要进行定向井压裂射孔方位优化。考虑原地应力、套管水泥环诱导应力、射孔孔眼诱导应力、井筒注液诱导应力和流体渗流诱导应力综合叠加,基于张性破坏准则,建立了基于最低裂缝起裂压力(FIP)的定向井压裂射孔方位优化模型;并进一步通过室内物理模拟,验证了模型的可靠性与合理性。模拟结果表明,FIP在360°射孔方位内周期性变化,存在两个最小和最大FIP点,并且随着井筒方位角的增加而增加,最小FIP逐渐增加,最大FIP逐渐减小;不同井斜角和方位角的最小FIP对应的射孔方向相差较大,斜井的最佳射孔方向应同时考虑井斜角和方位角的综合影响;水平主应力差和施工排量等因素对确定最佳射孔方位影响不大;并且在SXM气田X井进行了现场应用,优化的最佳射孔方向角为20°和205°,其对应的最小起裂压力为45.5 MPa。从而降低施工难度,为低渗储层射孔方位优化技术提供借鉴。

关键词：定向井原地应力诱导应力最小起裂压力最佳射孔方位