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The AVO Effect of Formation Pressure on Time-Lapse Seismic Monitoring in Marine Carbon Dioxide Storage
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作者 Fan Wu Qingping Li +1 位作者 Yufa He Jingye Li 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第3期645-655,共11页
The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the informatio... The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the information of formation pressure can be response in the seismic data. Therefore, it is possible to monitor the formation pressure using time-lapse seismic method. Apart from formation pressure, the information of porosity and CO_(2) saturation can be reflected in the seismic data. Here, based on the actual situation of the work area, a rockphysical model is proposed to address the feasibility of time-lapse seismic monitoring during CO_(2) storage in the anisotropic formation. The model takes into account the formation pressure, variety minerals composition, fracture, fluid inhomogeneous distribution, and anisotropy caused by horizontal layering of rock layers(or oriented alignment of minerals). From the proposed rockphysical model and the well-logging, cores and geological data at the target layer, the variation of P-wave and S-wave velocity with formation pressure after CO_(2) injection is calculated. And so are the effects of porosity and CO_(2) saturation. Finally, from anisotropic exact reflection coefficient equation, the reflection coefficients under different formation pressures are calculated. It is proved that the reflection coefficient varies with pressure. Compared with CO_(2) saturation, the pressure has a greater effect on the reflection coefficient. Through the convolution model, the seismic record is calculated. The seismic record shows the difference with different formation pressure. At present, in the marine CO_(2) sequestration monitoring domain, there is no study involving the effect of formation pressure changes on seismic records in seafloor anisotropic formation. This study can provide a basis for the inversion of reservoir parameters in anisotropic seafloor CO_(2) reservoirs. 展开更多
关键词 time-lapse seismic monitoring Marine carbon dioxide storage AVO modeling Formation pressure Anisotropic Rockphysical model
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Time-lapse培养与桌面台式培养箱胚胎培养对胚胎发育的影响
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作者 蔡冰红 谢晓俊 《智慧健康》 2024年第11期42-44,共3页
目的探讨Time-lapse培养与桌面台式培养箱胚胎培养对胚胎发育的影响。方法选取2021年3月—2023年3月在本院生殖中心行IVF-ET/ICSI-ET治疗的613个周期的胚胎发育数据,随机分配胚胎培养方式。分为对照组与研究组,其中对照组为桌面台式培... 目的探讨Time-lapse培养与桌面台式培养箱胚胎培养对胚胎发育的影响。方法选取2021年3月—2023年3月在本院生殖中心行IVF-ET/ICSI-ET治疗的613个周期的胚胎发育数据,随机分配胚胎培养方式。分为对照组与研究组,其中对照组为桌面台式培养箱方式(360个周期),研究组为Time-lapse培养与桌面台式培养箱方式(253个周期),统计两组胚胎发育质量。结果研究组中正常受精数、可移植胚胎数、形成囊胚数、优质胚胎数、高评分囊胚数、受精率、冷冻胚胎率、胚囊形成率、优质胚胎率、高评分囊胚率高于对照组,组间差异有统计学意义(P<0.05)。结论Time-lapse培养与桌面台式培养箱胚胎培养方式优于桌面台式培养箱方式,可为胚胎培养提供适宜的环境、温度、湿度等,有助于胚胎发育,具有较强的实用性和推广性,值得推广应用。 展开更多
关键词 time-lapse培养 桌面台式培养箱 胚胎培养 胚胎发育
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Landslide monitoring in southwestern China via time-lapse electrical resistivity tomography 被引量:12
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作者 徐冬 胡祥云 +1 位作者 单春玲 李睿恒 《Applied Geophysics》 SCIE CSCD 2016年第1期1-12,217,共13页
The dynamic monitoring of landslides in engineering geology has focused on the correlation among landslide stability,rainwater infiltration,and subsurface hydrogeology.However,the understanding of this complicated cor... The dynamic monitoring of landslides in engineering geology has focused on the correlation among landslide stability,rainwater infiltration,and subsurface hydrogeology.However,the understanding of this complicated correlation is still poor and inadequate.Thus,in this study,we investigated a typical landslide in southwestern China via time-lapse electrical resistivity tomography(TLERT) in November 2013 and August 2014.We studied landslide mechanisms based on the spatiotemporal characteristics of surface water infiltration and flow within the landslide body.Combined with borehole data,inverted resistivity models accurately defined the interface between Quaternary sediments and bedrock.Preferential flow pathways attributed to fracture zones and fissures were also delineated.In addition,we found that surface water permeates through these pathways into the slipping mass and drains away as fissure water in the fractured bedrock,probably causing the weakly weathered layer to gradually soften and erode,eventually leading to a landslide.Clearly,TLERT dynamic monitoring can provide precursory information of critical sliding and can be used in landslide stability analysis and prediction. 展开更多
关键词 time-lapse electrical resistivity tomography LANDSLIDE HYDROGEOPHYSICS MONITORING preferential flow
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使用time-lapse筛选早期IVF/ICSI胚胎及其临床结局 被引量:4
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作者 陈明颢 黄军 +1 位作者 钟影 全松 《南方医科大学学报》 CAS CSCD 北大核心 2015年第12期1760-1764,1781,共6页
目的通过比较使用time-lapse(延迟摄像)和传统形态学方法筛选IVF/ICSI胚胎的临床结局,评价time-lapse用于早期胚胎观察和筛选的价值。方法回顾性分析139个IVF/ICSI周期的资料,根据胚胎的筛选方法,分为time-lapse monitoring组(TLM组... 目的通过比较使用time-lapse(延迟摄像)和传统形态学方法筛选IVF/ICSI胚胎的临床结局,评价time-lapse用于早期胚胎观察和筛选的价值。方法回顾性分析139个IVF/ICSI周期的资料,根据胚胎的筛选方法,分为time-lapse monitoring组(TLM组)(n=68)和对照组(n=71),比较两组间的βHCG阳性率、临床妊娠率和胚胎着床率,并根据女方年龄、受精方式进行亚组分析。结果 TLM组的βHCG阳性率、临床妊娠率、胚胎着床率分别为:66.2%、61.8%、47.1%;对照组的βHCG阳性率、临床妊娠率、胚胎着床率分别为:47.9%、43.7%、30.3%;TLM组的βHCG阳性率、临床妊娠率、胚胎着床率均高于对照组,且差异均有统计学意义(P〈0.05)。亚组分析显示:相较于年龄≤30岁的患者,年龄31~35岁的患者利用time-lapse更能明显改善临床结局;利用time-lapse能明显提高IVF周期的βHCG阳性率、临床妊娠率、胚胎着床率,但对于ICSI和TESA周期,效果则不理想。结论使用time-lapse动态监测胚胎并根据胚胎的形态动力学参数对胚胎进行评价和筛选,与传统方法相比,能获得更好的临床结局;年龄较大的(〉30岁)或者是进行IVF周期的患者更能从中获益。 展开更多
关键词 time-lapse 传统形态学方法 胚胎筛选 临床妊娠率 胚胎着床率
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利用Time-lapse技术筛选早期胚胎对IVF-ET妊娠结局的影响 被引量:2
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作者 丁洁 孟庆霞 +5 位作者 郑爱燕 蒲艳 廖桂芝 许咏乐 李红 王玮 《生殖医学杂志》 CAS 2019年第8期872-877,共6页
目的探索利用Time-lapse系统筛选早期胚胎的临床应用价值。方法回顾性分析本中心2016年7月至2017年12月,第一次新鲜或复苏周期D3卵裂期胚胎移植的患者资料,根据胚胎评估方法分为Time-lapse系统组(TLM组,n=74)和传统形态学评分组(CMA组,n... 目的探索利用Time-lapse系统筛选早期胚胎的临床应用价值。方法回顾性分析本中心2016年7月至2017年12月,第一次新鲜或复苏周期D3卵裂期胚胎移植的患者资料,根据胚胎评估方法分为Time-lapse系统组(TLM组,n=74)和传统形态学评分组(CMA组,n=951),比较这两种不同胚胎筛选方法对临床结局的影响。结果患者的不孕年限、体重指数、基础FSH、基础LH、E2、AMH、窦卵泡数、内膜厚度和周期类型等一般情况,在TLM组和CMA组均无显著差异(P均>0.05);TLM组年龄显著高于CMA组[(31.8±4.2)vs.(30.8±4.4),P<0.05],而平均移植胚胎数显著少于CMA组[(1.7±0.5)vs.(1.9±0.3),P<0.05];患者的临床结局,包括临床妊娠率、种植率、流产率、宫外孕率、双胎率和移植两个胚胎的双胎率等在两组间均无显著差异(P均>0.05)。进一步按照年龄分层分析,在<35岁患者,患者的一般情况在两组间均无显著差异(P均>0.05),TML组的平均移植胚胎数显著少于CMA组[(1.7±0.5)vs.(1.9±0.3),P<0.05],而患者临床结局在两组间亦无显著差异(P>0.05);在≥35岁患者,TML组的平均移植胚胎数显著少于CMA组[(1.7±0.5)vs.(1.9±0.4),P<0.05],而患者的一般情况和临床结局在两组间亦无显著差异(P>0.05)。结论利用Time-lapse技术选择早期胚胎,可以在显著减少移植胚胎数的基础上,维持稳定的临床妊娠结局。因此,认为Time-lapse技术可以在一定程度上优选出更具发育潜能的胚胎,为早期胚胎单胚胎移植提供新方法。 展开更多
关键词 time-lapse 早期胚胎 临床妊娠率 种植率
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Time-lapse是否能预测胚胎染色体整倍性? 被引量:2
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作者 黄国宁 《生殖医学杂志》 CAS 2019年第11期1249-1250,共2页
Time-lapse技术推进了胚胎评估的方法学,为胚胎评估带来了新的视角。Time-lapse系统理论上应具有预测胚胎染色体整倍性的潜力,但还需临床研究证实。
关键词 time-lapse系统 染色体整倍性
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应用time-lapse技术探讨7~10细胞D3优质胚胎的发育潜能 被引量:2
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作者 张京业 刘辉 +3 位作者 李梅 王苗苗 陶文荣 吴克良 《现代妇产科进展》 CSCD 北大核心 2016年第11期825-829,共5页
目的:探讨人体外受精-胚胎移植(IVF-ET)中第3天细胞数目为7、8、9、10优质胚胎的发育潜能。方法:选取2014年11月至2015年10月于山东大学附属生殖医院行IVF-ET患者的D3(授精后第三天)胚胎,利用time-lapse(延时摄像)技术分析7~10... 目的:探讨人体外受精-胚胎移植(IVF-ET)中第3天细胞数目为7、8、9、10优质胚胎的发育潜能。方法:选取2014年11月至2015年10月于山东大学附属生殖医院行IVF-ET患者的D3(授精后第三天)胚胎,利用time-lapse(延时摄像)技术分析7~10细胞优质胚胎的早期分裂行为,进而探讨胚胎早期分裂行为对囊胚形成率和临床结局的影响。结果:(1)四种细胞数胚胎早期的分裂行为不同:大多数8细胞胚胎为发育正常(NB)的胚胎;9细胞和10细胞中发生直接分裂(DC,一种异常分裂)的胚胎比例高于发育正常胚胎;所有7细胞胚胎均存在异常分裂,其中主要为逆分裂(RC,一种异常分裂)和同步分裂延迟(t8-t5,S3,胚胎由5细胞分裂为8细胞的时间)。(2)与NB相比,每一种异常分裂(DC,RC,S3)的发生均不同程度降低了胚胎的发育潜能。(3)四种细胞数胚胎的发育结局显示,8细胞胚胎有最高的囊胚形成率和胚胎着床率,其次为9细胞和10细胞胚胎,7细胞胚胎的囊胚形成率和着床率最低。结论:7、8、9、10四种细胞数胚胎早期发育过程中异常分裂的类型和所占比重不同,最终导致其发育潜能的差异。8细胞胚胎的发育潜能最高,其次为9细胞和10细胞胚胎,7细胞胚胎发育潜能最低。 展开更多
关键词 time-lapse 早期分裂行为 发育潜能
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Purposeless repeated acquisition time-lapse seismic data processing 被引量:3
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作者 Li Jingye Chen Xiaohong +1 位作者 Zhao Wei Zhang Yunpeng 《Petroleum Science》 SCIE CAS CSCD 2008年第1期31-36,共6页
In China, most oil fields are continental sedimentation with strong heterogeneity, which on one side makes the reservoir prospecting and development more difficult, but on the other side provides more space for search... In China, most oil fields are continental sedimentation with strong heterogeneity, which on one side makes the reservoir prospecting and development more difficult, but on the other side provides more space for searching residual oil in matured fields. Time-lapse seismic reservoir monitoring technique is one of most important techniques to define residual oil distribution. According to the demand for and development of time-lapse seismic reservoir monitoring in China, purposeless repeated acquisition time-lapse seismic data processing was studied. The four key steps in purposeless repeated acquisition time-lapse seismic data processing, including amplitude-preserved processing with relative consistency, rebinning, match filtering and difference calculation, were analyzed by combining theory and real seismic data processing. Meanwhile, quality control during real time-lapse seismic processing was emphasized. 展开更多
关键词 time-lapse seismic purposeless repeated acquisition rebinning match filtering amplitude-preserved processing
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Influence of Different Quality Sperm on Early Embryo Morphokinetic Parameters and Cleavage Patterns:A Retrospective Time-lapse Study 被引量:2
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作者 Qiu-yue LIAO Bo HUANG +4 位作者 Si-jia ZHANG Jing CHEN Ge CHEN Ke-zhen LI Ji-hui AI 《Current Medical Science》 SCIE CAS 2020年第5期960-967,共8页
To investigate whether sperm with low concentration and motility can impact preimplantation embryos and to analyze how the effects present under a time-lapse incubation system,2905 oocytes were collected from 219 coup... To investigate whether sperm with low concentration and motility can impact preimplantation embryos and to analyze how the effects present under a time-lapse incubation system,2905 oocytes were collected from 219 couples between January 2014 and December 2015.Patients were divided into three groups according to sperm quality.Morphokinetic parameters and six cleavage patterns in the initial three cleavages were evaluated using the Primo Vision system.Embryo quality and clinic outcomes such as implantation rate,pregnancy rate and live birth rate were measured.The results showed that the concentration and motility of sperm correlated strongly with the rate of 2PN embryos,good-quality embryos on D3,blastocysts on D5/6 and good quality embryos on D5/6.The time-lapse system recordings showed that compromised sperm quality could result in a significant delay in cc l and a decrease in cc2,and impact embryo developmental potential mainly through large fragments or/and blastomere fragmentation in the initial three cleavages.In conclusion,sperm with low concentration and motility can have paternal effects on preimplantation embryos.These paternal effects present both as changes in morphokinetic parameters and cleavage patterns,which occur as early as fertilization and may cause severe damage to the preimplantation embryos. 展开更多
关键词 embryo development patermal effect time-lapse morphokinetic parameters cleavage patterns
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Monitoring the change in horizontal stress with multi-wave time-lapse seismic response based on nonlinear elasticity theory 被引量:2
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作者 Fu-Bin Chen Zhao-Yun Zong Xing-Yao Yin 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期815-826,共12页
Monitoring the change in horizontal stress from the geophysical data is a tough challenge, and it has a crucial impact on broad practical scenarios which involve reservoir exploration and development, carbon dioxide (... Monitoring the change in horizontal stress from the geophysical data is a tough challenge, and it has a crucial impact on broad practical scenarios which involve reservoir exploration and development, carbon dioxide (CO_(2)) injection and storage, shallow surface prospecting and deep-earth structure description. The change in in-situ stress induced by hydrocarbon production and localized tectonic movements causes the changes in rock mechanic properties (e.g. wave velocities, density and anisotropy) and further causes the changes in seismic amplitudes, phases and travel times. In this study, the nonlinear elasticity theory that regards the rock skeleton (solid phase) and pore fluid as an effective whole is used to characterize the effect of horizontal principal stress on rock overall elastic properties and the stress-dependent anisotropy parameters are therefore formulated. Then the approximate P-wave, SV-wave and SH-wave angle-dependent reflection coefficient equations for the horizontal-stress-induced anisotropic media are proposed. It is shown that, on the different reflectors, the stress-induced relative changes in reflectivities (i.e., relative difference) of elastic parameters (i.e., P- and S-wave velocities and density) are much less than the changes in contrasts of anisotropy parameters. Therefore, the effects of stress change on the reflectivities of three elastic parameters are reasonably neglected to further propose an AVO inversion approach incorporating P-, SH- and SV-wave information to estimate the change in horizontal principal stress from the corresponding time-lapse seismic data. Compared with the existing methods, our method eliminates the need for man-made rock-physical or fitting parameters, providing more stable predictive power. 1D test illustrates that the estimated result from time-lapse P-wave reflection data shows the most reasonable agreement with the real model, while the estimated result from SH-wave reflection data shows the largest bias. 2D test illustrates the feasibility of the proposed inversion method for estimating the change in horizontal stress from P-wave time-lapse seismic data. 展开更多
关键词 Monitoring change in horizontal stress Multi-wave reflection coefficients Nonlinear elasticity theory time-lapse seismic data
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应用Time-lapse研究人3PN胚胎的卵裂模式 被引量:1
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作者 史艳彬 马超 +1 位作者 余巧巧 邵小光 《生殖医学杂志》 CAS 2019年第10期1158-1161,共4页
目的比较IVF3PN、IVF2PN、ICSI3PN和ICSI2PN胚胎的卵裂模式和胚胎动力学参数的差异。方法回顾性分析2017年7月至2018年6月在我院生殖中心就诊经时差胚胎监测(Time-lapse)培养箱培养的393个胚胎发育动力学参数,根据受精结局分为4组:IVF3P... 目的比较IVF3PN、IVF2PN、ICSI3PN和ICSI2PN胚胎的卵裂模式和胚胎动力学参数的差异。方法回顾性分析2017年7月至2018年6月在我院生殖中心就诊经时差胚胎监测(Time-lapse)培养箱培养的393个胚胎发育动力学参数,根据受精结局分为4组:IVF3PN组(n=132)、IVF2PN组(n=150)、ICSI3PN组(n=11)和ICSI2PN组(n=100),分析比较各组胚胎的卵裂模式和原核出现时间、原核消失时间、第一次卵裂时间、t4、t3-t5等胚胎动力学参数。结果IVF3PN组胚胎第一次卵裂模式异常率(100%)显著高于IVF2PN组胚胎(4.67%)、ICSI3PN组胚胎(18.18%)和ICSI2PN组胚胎(5.00%)(P<0.001),而ICSI3PN组、ICSI2PN组和IVF2PN组胚胎之间的第一次卵裂模式异常率无显著差异(P>0.05)。IVF3PN组胚胎原核消失时间[(25.76±1.33)h]显著长于IVF2PN组[(21.43±1.76)h]、ICSI3PN组[(21.86±1.63)h]和ICSI2PN组[(20.14±1.78)h](P<0.05),IVF3PN胚胎第一次卵裂时间亦显著长于其余3组[(27.06±1.59)hvs.(22.64±1.38)h、(22.32±1.56)h、(22.78±1.66)h](P<0.05);ICSI3PN组、ICSI2PN组和IVF2PN组胚胎之间的原核消失时间和第一次卵裂时间均无显著差异(P>0.05)。结论IVF3PN胚胎与IVF2PN、ICSI3PN和ICSI2PN胚胎的卵裂模式和原核消失时间、第一次卵裂时间等动力学参数不同。 展开更多
关键词 time-lapse 人胚胎 三原核 卵裂模式 胚胎动力学
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Time-lapse培养与传统胚胎培养胚胎发育和临床结局比较以及Time-lapse早期胚胎形态动力学参数应用探讨 被引量:1
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作者 冯播 邱峰龙 +3 位作者 仲纪祥 曹森杨 张荣雪 左阳花 《中国性科学》 2022年第11期108-111,共4页
目的比较Time-lapse及传统胚胎培养对体外受精-胚胎移植(IVF-ET)患者胚胎发育情况及临床结局的影响,探讨Time-lapse胚胎形态动力学参数的应用价值。方法选取扬州大学医学院附属淮安市妇幼保健院142对接受IVF-ET治疗的夫妇的临床资料进... 目的比较Time-lapse及传统胚胎培养对体外受精-胚胎移植(IVF-ET)患者胚胎发育情况及临床结局的影响,探讨Time-lapse胚胎形态动力学参数的应用价值。方法选取扬州大学医学院附属淮安市妇幼保健院142对接受IVF-ET治疗的夫妇的临床资料进行回顾性分析,共纳入142个IVF-ET新鲜周期,按照胚胎培养方法分为观察组(n=55)和对照组(n=87)。观察组采用Time-lapse培养箱进行胚胎培养;对照组采用传统培养系统进行胚胎培养。比较两组的获卵数、正常受精数、可移植胚胎数、优质胚胎数、冷冻数及临床妊娠率等指标。比较观察组种植胚胎与未种植胚胎早期胚胎形态动力学参数(t2、t3、t4、t5、cc2及s2),采用受试者工作特征(ROC)曲线评估有差异的时间参数对胚胎种植失败的预测价值。结果观察组可移植胚胎数及囊胚形成数显著高于对照组(P<0.05)。种植胚胎t2、t4、s2、cc2均显著短于未种植胚胎(P<0.05);但t3和t5比较,差异无统计学意义(P>0.05)。ROC曲线显示,t2、t4、s2、cc2对胚胎种植失败有预测价值。结论IVF-ET患者胚胎受精后采用Time-lapse培养,能够提高可移植胚胎数及形成囊胚数;部分早期胚胎动力学参数对新鲜周期移植失败具有一定的预测价值。 展开更多
关键词 time-lapse培养 传统培养 体外受精-胚胎移植 妊娠结局
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Human blastomere rotation in early cleavage embryos is not associated with reduced implantation: Evidence from time-lapse videography
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作者 Emma P Langdon Yan-he Liu +1 位作者 Phillip L Matson Peter J Mark 《Asian pacific Journal of Reproduction》 2019年第6期297-298,共2页
Dear Editor,Time-lapse videography of human embryos allows for the easy visualization of the embryos without removing them from the protective environment of the incubator[1],the measurement of various morphokinetic(q... Dear Editor,Time-lapse videography of human embryos allows for the easy visualization of the embryos without removing them from the protective environment of the incubator[1],the measurement of various morphokinetic(quantitative)parameters[2],and the identification of abnormalities of growth(qualitative parameters)such as direct cleavage[3],reverse cleavage[4]and intercellular contact of blastomeres[5]. 展开更多
关键词 HUMAN embryos BLASTOMERE ROTATION time-lapse videography
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Time-lapse videography reveals different morphokinetic profiles of human embryos displaying direct or reverse cleavage at different stages of development: A retrospective sibling embryo study
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作者 Chloé Brits Katie Feenan +2 位作者 Vince Chapple Phillip L.Matson Yan-he Liu 《Asian pacific Journal of Reproduction》 2020年第6期261-266,共6页
Objective:To investigate morphokinetic characteristics of embryos displaying either reverse cleavage or direct cleavage during the first,second or third cleavage cycle.Methods:A total of 167 in vitro fertilization and... Objective:To investigate morphokinetic characteristics of embryos displaying either reverse cleavage or direct cleavage during the first,second or third cleavage cycle.Methods:A total of 167 in vitro fertilization and/or intracytoplasmic sperm injection treatment cycles undertaken by 167 women[aged(35.0±4.6)years]were included for reverse cleavage analysis,and a total of 167 in vitro fertilization and/or intracytoplasmic sperm injection treatment cycles undertaken by 167 women[aged(33.8±4.3)years]were included for direct cleavage analysis in this study.Using a sibling-embryo design,morphokinetic profiles(both before and after the onset of abnormal event)of embryos displaying reverse cleavage(n=241)or direct cleavage(n=244)were compared with their unaffected siblings(the controls)in the first,second and third cell cycles(n=32,n=142,n=562;n=195,n=412,n=205,respectively),at different developmental stages up to day 3.Results:Direct cleavage embryos demonstrated significantly delayed cleavage rates prior to the event regardless of developmental stage of the occurrence,while reverse cleavage embryos showed similar cleavage rates to their unaffected siblings.Post event,direct cleavage embryos sped up cleavage rates while reverse cleavage embryos slowed down.Conclusions:Altered morphokinetic profiles are displayed by direct cleavage embryos both before and after their occurrence and reverse cleavage embryos after the occurrence,which could potentially confound morphokinetic comparisons if not separated from their unaffected sibling embryos.Further study is warranted in order to fully understand the biological mechanisms of such events. 展开更多
关键词 time-lapse Direct cleavage Reverse cleavage Morphokinetics Cleavage abnormality
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Quantitative prediction of oil saturation of unconsolidated sandstone reservoir based on time-lapse seismic “relative difference method”: Taking Zeta oil field in West Africa as an example
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作者 LU Hongmei XU Hai +1 位作者 WO Yujin GU Ning 《Petroleum Exploration and Development》 2019年第2期426-434,共9页
In view of the disadvantage that the absolute difference of time-lapse seismic(the difference between monitoring data and base data) is not only related to the change of oil saturation, but also closely related to the... In view of the disadvantage that the absolute difference of time-lapse seismic(the difference between monitoring data and base data) is not only related to the change of oil saturation, but also closely related to the thickness of reservoir, a time-lapse seismic "relative difference method"(the ratio of monitoring data to base data) not affected by the thickness of reservoir but only related to the change of fluid saturation, is proposed through seismic forward modeling after fluid displacement simulation. Given the same change of fluid saturation, the absolute difference of time-lapse seismic conforms to the law of "tuning effect" and seismic reflection of "thin bed", and the remaining oil prediction method based on absolute difference of time-lapse seismic is only applicable to the reservoirs with uniform thickness smaller than the tuning thickness or with thickness greater than the tuning thickness. The relative difference of time-lapse seismic is not affected by reservoir thickness, but only related to the change of fluid saturation. It is applicable to all the deep-sea unconsolidated sandstone reservoirs which can exclude the effect of pressure, temperature, pore type and porosity on seismic. Therefore, the relation between the relative difference of time-lapse seismic and the change of fluid saturation, which is obtained from seismic forward modeling after Gassmann fluid displacement simulation, can be used to quantitatively predict the change of reservoir water saturation and then the distribution of the remaining oil. The application of this method in deep sea Zeta oil field in west Africa shows that it is reasonable and effective. 展开更多
关键词 time-lapse seismic remaining OIL quantitative prediction unconsolidated sandstone reservoir fluid displacement absolute DIFFERENCE RELATIVE DIFFERENCE ZETA OIL field WEST AFRICA
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Source Camera Identification Algorithm Based on Multi-Scale Feature Fusion
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作者 Jianfeng Lu Caijin Li +2 位作者 Xiangye Huang Chen Cui Mahmoud Emam 《Computers, Materials & Continua》 SCIE EI 2024年第8期3047-3065,共19页
The widespread availability of digital multimedia data has led to a new challenge in digital forensics.Traditional source camera identification algorithms usually rely on various traces in the capturing process.Howeve... The widespread availability of digital multimedia data has led to a new challenge in digital forensics.Traditional source camera identification algorithms usually rely on various traces in the capturing process.However,these traces have become increasingly difficult to extract due to wide availability of various image processing algorithms.Convolutional Neural Networks(CNN)-based algorithms have demonstrated good discriminative capabilities for different brands and even different models of camera devices.However,their performances is not ideal in case of distinguishing between individual devices of the same model,because cameras of the same model typically use the same optical lens,image sensor,and image processing algorithms,that result in minimal overall differences.In this paper,we propose a camera forensics algorithm based on multi-scale feature fusion to address these issues.The proposed algorithm extracts different local features from feature maps of different scales and then fuses them to obtain a comprehensive feature representation.This representation is then fed into a subsequent camera fingerprint classification network.Building upon the Swin-T network,we utilize Transformer Blocks and Graph Convolutional Network(GCN)modules to fuse multi-scale features from different stages of the backbone network.Furthermore,we conduct experiments on established datasets to demonstrate the feasibility and effectiveness of the proposed approach. 展开更多
关键词 Source camera identification camera forensics convolutional neural network feature fusion transformer block graph convolutional network
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Ultrafast pulse-dilation framing camera and its application for time-resolved X-ray diagnostic
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作者 Hou-Zhi Cai Qiu-Yan Luo +10 位作者 Kai-Xuan Lin Xuan Deng Jun-Kai Liu Kai-Zhi Yang Dong Wang Jia-Jie Chen Jia-Heng Wang Jing-Hua Long Li-Hong Niu Yun-Fei Lei Jin-Yuan Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期101-114,共14页
An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were reported.The camera achieved a temporal resolution of 10 ps by using a pulse-dilation devi... An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were reported.The camera achieved a temporal resolution of 10 ps by using a pulse-dilation device and gated MCP imager,and a spatial resolution of 100μm by using an electronic imaging system comprising combined magnetic lenses.The spatial resolution characteristics of the camera were studied both theoretically and experimentally.The results showed that the camera with combined magnetic lenses reduced the field curvature and acquired a larger working area.A working area with a diameter of 53 mm was created by applying four magnetic lenses to the camera.Furthermore,the camera was used to detect the X-rays produced by the laser-targeting device.The diagnostic results indicated that the width of the X-ray pulse was approximately 18 ps. 展开更多
关键词 Inertial confinement fusion Plasma diagnostics Framing camera Combined lenses Pulse-dilation
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Monocular Distance Estimated Based on PTZ Camera
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作者 Qirui Zhong Xiaogang Cheng +1 位作者 Yuxin Song Han Wang 《Computers, Materials & Continua》 SCIE EI 2024年第5期3417-3433,共17页
This paper introduces an intelligent computational approach for extracting salient objects fromimages and estimatingtheir distance information with PTZ (Pan-Tilt-Zoom) cameras. PTZ cameras have found wide applications... This paper introduces an intelligent computational approach for extracting salient objects fromimages and estimatingtheir distance information with PTZ (Pan-Tilt-Zoom) cameras. PTZ cameras have found wide applications innumerous public places, serving various purposes such as public securitymanagement, natural disastermonitoring,and crisis alarms, particularly with the rapid development of Artificial Intelligence and global infrastructuralprojects. In this paper, we combine Gauss optical principles with the PTZ camera’s capabilities of horizontal andpitch rotation, as well as optical zoom, to estimate the distance of the object.We present a novel monocular objectdistance estimation model based on the Focal Length-Target Pixel Size (FLTPS) relationship, achieving an accuracyrate of over 95% for objects within a 5 km range. The salient object extraction is achieved through a simplifiedconvolution kernel and the utilization of the object’s RGB features, which offer significantly faster computingspeeds compared to Convolutional Neural Networks (CNNs). Additionally, we introduce the dark channel beforethe fog removal algorithm, resulting in a 20 dB increase in image definition, which significantly benefits distanceestimation. Our system offers the advantages of stability and low device load, making it an asset for public securityaffairs and providing a reference point for future developments in surveillance hardware. 展开更多
关键词 Public security location information PTZ camera image processing
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Automatic Miscalibration Detection and Correction of LiDAR and Camera Using Motion Cues
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作者 Pai Peng Dawei Pi +3 位作者 Guodong Yin Yan Wang Liwei Xu Jiwei Feng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期318-329,共12页
This paper aims to develop an automatic miscalibration detection and correction framework to maintain accurate calibration of LiDAR and camera for autonomous vehicle after the sensor drift.First,a monitoring algorithm... This paper aims to develop an automatic miscalibration detection and correction framework to maintain accurate calibration of LiDAR and camera for autonomous vehicle after the sensor drift.First,a monitoring algorithm that can continuously detect the miscalibration in each frame is designed,leveraging the rotational motion each individual sensor observes.Then,as sensor drift occurs,the projection constraints between visual feature points and LiDAR 3-D points are used to compute the scaled camera motion,which is further utilized to align the drifted LiDAR scan with the camera image.Finally,the proposed method is sufficiently compared with two representative approaches in the online experiments with varying levels of random drift,then the method is further extended to the offline calibration experiment and is demonstrated by a comparison with two existing benchmark methods. 展开更多
关键词 Autonomous vehicle LiDAR and camera Miscalibration detection and correction Sensor drift
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Imaging simulation and analysis of attitude jitter effect on topographic mapping for lunar orbiter stereo optical cameras
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作者 CHEN Chen TONG Xiao-Hua +4 位作者 LIU Shi-Jie YE Zhen HUANG Chao-Wei WU Hao ZHANG Han 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2024年第5期722-730,共9页
The geometric accuracy of topographic mapping with high-resolution remote sensing images is inevita-bly affected by the orbiter attitude jitter.Therefore,it is necessary to conduct preliminary research on the stereo m... The geometric accuracy of topographic mapping with high-resolution remote sensing images is inevita-bly affected by the orbiter attitude jitter.Therefore,it is necessary to conduct preliminary research on the stereo mapping camera equipped on lunar orbiter before launching.In this work,an imaging simulation method consid-ering the attitude jitter is presented.The impact analysis of different attitude jitter on terrain undulation is conduct-ed by simulating jitter at three attitude angles,respectively.The proposed simulation method is based on the rigor-ous sensor model,using the lunar digital elevation model(DEM)and orthoimage as reference data.The orbit and attitude of the lunar stereo mapping camera are simulated while considering the attitude jitter.Two-dimensional simulated stereo images are generated according to the position and attitude of the orbiter in a given orbit.Experi-mental analyses were conducted by the DEM with the simulated stereo image.The simulation imaging results demonstrate that the proposed method can ensure imaging efficiency without losing the accuracy of topographic mapping.The effect of attitude jitter on the stereo mapping accuracy of the simulated images was analyzed through a DEM comparison. 展开更多
关键词 topographic mapping lunar orbiter stereo camera attitude jitter imaging simulation digital elevation model
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