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Bone block from lateral window-correcting vertical and horizontal bone deficiency in maxilla posterior site:A case report
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作者 Yu-Lan Wang Wen-Jun Shao Min Wang 《World Journal of Clinical Cases》 SCIE 2024年第12期2109-2115,共7页
BACKGROUND Lateral window approach for sinus floor lift is commonly used for vertical bone augmentation in cases when the residual bone height is less than 5 mm.However,managing cases becomes more challenging when a m... BACKGROUND Lateral window approach for sinus floor lift is commonly used for vertical bone augmentation in cases when the residual bone height is less than 5 mm.However,managing cases becomes more challenging when a maxillary sinus pseudocyst is present or when there is insufficient bone width.In this case,we utilized the bone window prepared during the lateral window sinus lift as a shell for horizontal bone augmentation.This allowed for simultaneous horizontal and vertical bone augmentation immediately after the removal of the maxillary sinus pseudocyst.CASE SUMMARY A 28-year-old female presented to our clinic with the chief complaint of missing upper left posterior teeth.Intraoral examination showed a horizontal deficiency of the alveolar ridge contour.The height of the alveolar bone was approximately 3.6 mm on cone beam computed tomography(CBCT).And a typical well-defined'dome-shaped'lesion in maxillary sinus was observed on CBCT imaging.The lateral bony window was prepared using a piezo-ultrasonic device,then the bony window was fixed to the buccal side of the 26 alveolar ridge using a titanium screw with a length of 10 mm and a diameter of 1.5 mm.The space between the bony window and the alveolar ridge was filled with Bio-Oss,covered with a Bio-Gide collagen membrane,and subsequently sutured.Nine months later,the patient’s bone width increased from 4.8 to 10.5 mm,and the bone height increased from 3.6 to 15.6 mm.Subsequently,a Straumann^(■)4.1 mm×10 mm implant was placed.The final all-ceramic crown restoration was completed four months later,and both clinical and radiographic examinations showed that the implant was successful,and the patient was satisfied with the results.CONCLUSION The bone block harvested from the lateral window sinus lift can be used for simultaneous horizontal bone augmentation acting as a shell for good two-dimensional bone augmentation. 展开更多
关键词 Sinus lift Lateral window Dental implant Horizontal bone augmentation Case report
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Evaluation of Well Spacing for Primary Development of Fractured Horizontal Wells in Tight Sandstone Gas Reservoirs
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作者 Fang Li Juan Wu +3 位作者 Haiyong Yi Lihong Wu Lingyun Du Yuan Zeng 《Fluid Dynamics & Materials Processing》 EI 2024年第5期1015-1030,共16页
Methods for horizontal well spacing calculation in tight gas reservoirs are still adversely affected by the complexity of related control factors,such as strong reservoir heterogeneity and seepage mechanisms.In this s... Methods for horizontal well spacing calculation in tight gas reservoirs are still adversely affected by the complexity of related control factors,such as strong reservoir heterogeneity and seepage mechanisms.In this study,the stress sensitivity and threshold pressure gradient of various types of reservoirs are quantitatively evaluated through reservoir seepage experiments.On the basis of these experiments,a numerical simulation model(based on the special seepage mechanism)and an inverse dynamic reserve algorithm(with different equivalent drainage areas)were developed.The well spacing ranges of Classes I,II,and III wells in the Q gas field are determined to be 802–1,000,600–662,and 285–400 m,respectively,with their average ranges as 901,631,and 342.5 m,respectively.By considering both the pairs of parallel well groups and series well groups as examples,the reliability of the calculation results is verified.It is shown that the combination of the two models can reduce errors and provide accurate results. 展开更多
关键词 Well spacing for primary development tight gas reservoir fractured horizontal well threshold pressure gradient stress sensitivity
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Analysis on the Observation Data of Three Profiles across the Qilian Mountain-Haiyuan Fault Zone
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作者 Hu Yaxuan Wang Xiong Cui Duxin Zhu Yiqing 《Earthquake Research in China》 2011年第4期486-497,共12页
由分析 GPS,铺平并且从 Minle, Huazangsi 和 Shagouhe 的严肃观察数据在 2005 期间介绍 Qilian Mountain-Haiyuan 差错到对面 - 2009,这些数据的变化和在不同时间的主要差错的活动特征被获得。Changma-Erbo, Maomaoshan, Zhunglan... 由分析 GPS,铺平并且从 Minle, Huazangsi 和 Shagouhe 的严肃观察数据在 2005 期间介绍 Qilian Mountain-Haiyuan 差错到对面 - 2009,这些数据的变化和在不同时间的主要差错的活动特征被获得。Changma-Erbo, Maomaoshan, Zhunglanghe 和 Haiyuan 指责的结果表演在最近的年里是活跃的。在垂直排水量和活动严肃数据之间的关系被分析,并且结果表明严肃变化主要由于集体转移。水平运动速度的方向几乎沿着差错的 GPS 观察表演的结果在 2006 罢工 - 2007 当水平速度在 2007 从差错方向背离了时 - 2008,由增加的东方排水量描绘了。在连续观察的 N 和 E 坐标值的时间系列上的线性趋势的移动之上的进一步的分析在三侧面附近中国的外壳的运动观察网络驻扎表明 Wenchuan 地震在 2007 在观察上有效果 - 2008。在 2008 比较重力的变化 - 2009 与 Bouguer 严肃异例背景,我们发现 Minle 侧面附近的区域在调整和恢复的阶段,当异例完全没在 Huazangsi 和 Shagouhe 侧面附近被恢复时。 展开更多
关键词 海原断裂带 观测数据 配置文件 祁连山 数据分析 布格重力异常 重力数据 垂直位移
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Three-dimensional crustal movement and the activities of earthquakes,volcanoes and faults in Hainan Island,China 被引量:8
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作者 Yaxuan Hu Ming Hao +1 位作者 Lingyun Ji Shangwu Song 《Geodesy and Geodynamics》 2016年第4期284-294,共11页
Hainan Island is a seismic active region, where Qiongshan M7.5 earthquake occurred in 1605 and several seismic belts appeared in recent years, especially the NS trending seismic belt (NSB) located in the northeast p... Hainan Island is a seismic active region, where Qiongshan M7.5 earthquake occurred in 1605 and several seismic belts appeared in recent years, especially the NS trending seismic belt (NSB) located in the northeast part of the island. Here is also a magmatic active region. The lava from about 100 volcanoes covered more than 4000 km^2. The latest eruptions occurred on Ma'anling-Lei Huling volcanoes within 10,000 years. The neotectonic movement has been determined by geological method in the island and its adjacent areas. In the paper, the present-day 3D crustal movement is obtained by using Global Positioning System (GPS) data observed from 2009 to 2014 and leveling observations measured in 1970s and 1990s respectively. The results show the horizontal movement is mainly along SEE direction relative to the Eurasian Plate. The velocities are between 4.01 and 6.70 mm/a. The tension rate near the NSB is less than I mm/a. The vertical movement shows the island uplifts as a whole with respect to the reference benchmark Xiuyinggang. The average uplifting rate is 2.4 mm/a. The rates are 2-3 mm/a in the northwest and 3-5mm/a in the northwest. It shows the deformation pattern of the southwest island is upward relative to the northeast, which is different from the result inferred from the coastal change and GPS. Haikou and its adjacent region present a subsidence in a long time. The southern part of the middle segment of the Wangwu-Wenjiao fault uplifts relative to the northern. Meanwhile, the western part uplifts relative to the eastern NSB. The vertical crustal motion and the two normal faults nearly correspond to the terrain. The NSB is located along the Puqiangang-Dazhibo fault, which is assessed as a segmented fault with a dip of 80°-90° and party exposed. The 3D deformations and other studies reveal the present activities of earthquakes, volcanoes and the faults. The small earthquakes will still occur in the NS belt and the volcanoes are not active now. 展开更多
关键词 Hainan Island Horizontal movement Vertical movement EARTHQUAKE VOLCANO FAULT Seismic belt
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Research and application on three-dimensional seismic and vibration isolation for building 被引量:5
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作者 魏陆顺 周福霖 +1 位作者 谭平 任珉 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第1期62-66,共5页
This paper presents the study of a three-dimensional(3D) isolation system.Firstly,the authors investigated the effects of an innovative 3D isolator,which was composed of a connecting plate,a rubber pad for vibration i... This paper presents the study of a three-dimensional(3D) isolation system.Firstly,the authors investigated the effects of an innovative 3D isolator,which was composed of a connecting plate,a rubber pad for vibration isolation in the vertical direction and a horizontal rubber bearing for seismic isolation in both horizontal directions.Secondly,the authors designed such a vibration isolation system and installed it underneath two specific residential buildings which were built directly over an existing subway communication hub platform in Beijing.These buildings required good performance vibration and seismic isolation system to reduce the impact from the running of nearby subway trains.Finally,in situ tests were conducted for both the isolated and the non-isolated buildings for the purpose of comparison.The test results showed that the maximum acceleration response level of the isolated superstructure is reduced by 10% as compared to that of the platform.The maximum attenuation of vibration reaches up to 25 dB.The 3D system explored in this paper is very effective in control and suppression of building vibration induced by earthquakes or running of trains. 展开更多
关键词 three-dimensional seismic and vibration isolator vertical vibration isolation horizontal seismic isolation engineering application
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Dynamic mechanism for horizontal deformation in part of North China area——Three-dimensional finite-element calculation and analysis of results from GPS remeasurement 被引量:1
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作者 黄立人 马青 +2 位作者 郭良迁 宋惠珍 刘洁 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第1期55-62,共8页
A deformation monitoring network that covers part of North China area and takes the Beijing region as the center was measured for two times with high precision GPS in 1995 and 1996 respectively. The results from reme... A deformation monitoring network that covers part of North China area and takes the Beijing region as the center was measured for two times with high precision GPS in 1995 and 1996 respectively. The results from remeasurement indicate that present horizontal movement in the monitored area is characterized by relative motion among several main tectonic blocks. Considering the spatial distribution features obtained from geological survey and results on seismic wave and activity in the area, and stratified features of crustal medium in depth, a three dimensional finite element medium model is designed. And under the conditions of taking and not taking the action manner of the background stress field in the studied area into account, the relative motion between tectonic blocks is calculated and modeled. Based on the results from the analysis and calculations the dynamic mechanism for the present horizontal deformation in the area is discussed. 展开更多
关键词 GPS measurement horizontal deformation three dimensional finite element
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Risk Assessment of Deep-Water Horizontal X-Tree Installation 被引量:1
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作者 MENG Wen-bo FU Guang-ming +3 位作者 HUANG Yi LIU Shu-jie HUANG Liang GAOYong-hai 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期210-220,共11页
Due to the high potential risk and many influencing factors of subsea horizontal X-tree installation,to guarantee the successful completion of sea trials of domestic subsea horizontal X-trees,this paper established a ... Due to the high potential risk and many influencing factors of subsea horizontal X-tree installation,to guarantee the successful completion of sea trials of domestic subsea horizontal X-trees,this paper established a modular risk evaluation model based on a fuzzy fault tree.First,through the analysis of the main process oftree down and combining the Offshore&Onshore Reliability Data(OREDA)failure statistics and the operation procedure and the data provided by the job,the fault tree model of risk analysis of the tree down installation was established.Then,by introducing the natural language of expert comprehensive evaluation and combining fuzzy principles,quantitative analysis was carried out,and the fuzzy number was used to calculate the failure probability of a basic event and the occurrence probability of a top event.Finally,through a sensitivity analysis of basic events,the basic events of top events significantly affected were determined,and risk control and prevention measures for the corresponding high-risk factors were proposed for subsea horizontal X-tree down installation. 展开更多
关键词 subsea horizontal X-tree risk assessment fuzzy fault tree modular risk evaluation model
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Present three-dimensional crustal deformation in Hainan Island 被引量:3
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作者 Hu Yaxuan Hu Jiuchang Hao Ming 《Geodesy and Geodynamics》 2014年第2期32-37,共6页
Hainan Island,located at the southeast edge of the Eurasian Plate,is affected by the motion of multiple plates,with its northeast edge mainly dilatating and its western margin presently compressing. By analyzing the G... Hainan Island,located at the southeast edge of the Eurasian Plate,is affected by the motion of multiple plates,with its northeast edge mainly dilatating and its western margin presently compressing. By analyzing the GPS rates during 1999- 2007 in Hainan and its adjacent region,we determined horizontal movement rates of 3. 0-21. 1 mm /a at the west of 104°E,evidently affected by the Indian Plate extrusion.Their directions are SE-SN-SW from east to west and are separated by the main fault. The principal strains have the same characteristics. The stations east of 104°E move mainly in the SEE direction. The eastward rates are 2. 1-8. 5 mm /a and northward rates are 0. 4- 2. 7 mm /a. The GPS rates during 2009- 2013 show that stations at the edge of the island move SEE relative to the Eurasian Plate,with rates relative to the mean benchmark,indicating that there are small relative movements between stations,whereas QION station,located in the middle,moves in the NW direction at a greater rate. Vertical differential movement is apparent in the northeast zone of the island. Upwelling of mantle plume material possibly influences the local stress.Three-dimensional GPS rates indicate that,at present,inherited crustal movement is dominant in Hainan. 展开更多
关键词 horizontal movement vertical movement principal strain crustal movement background Hainan aera
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Three-dimensional crustal deformation before and after the Wenchuan earthquake in Guanzhong and adjacent regions 被引量:1
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作者 Hu Yaxuan Qin Shanlan Hao Ming 《Geodesy and Geodynamics》 2015年第1期16-24,共9页
The recent plethora of GPS observations compensates for the 20-year-old lack in vertical displacement data for the Guanzhong region. The 2001—2007 three-dimensional(3D) crustal deformation data suggest regional mov... The recent plethora of GPS observations compensates for the 20-year-old lack in vertical displacement data for the Guanzhong region. The 2001—2007 three-dimensional(3D) crustal deformation data suggest regional movement with a horizontal velocity of 3—7 mm/a,predominantly from SSE in the west to SE in the east, and vertical inherited movement with velocity of -7 mm/a to 4 mm/a. After the Wenchuan earthquake, the GPS data suggest that the effect of the earthquake on the regional deformation is greater in the west than the east.The horizontal displacement increased during 2007—2008; however, the reverse was observed in 2008—2009. The vertical displacement in the western part of the region increased in 2008 and has been gradually returning to normal since 2009; however, in the eastern part,the effect of the earthquake remains. 展开更多
关键词 Horizontal movement Vertical movement Guanzhong area Wenchuan earthquake Geodynamics GPS(Global Position System)
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Anatomical adaptations of three species of Chinese xerophytes (Zygophyllaceae) 被引量:4
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作者 YANG Shu-min FURUKAWA Ikuo 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期247-251,共5页
第二等的木部特征和水平变化在三 xerophytic 种被描述, Zygophyllum xanthoxylon, Nitraria tangutorum,到西方的中国的蒺藜科土著人的 Tetraena 蒙古人集成通信适配器。所有种类让明显的生长除了,包围边界在 T 有时不连续。蒙古... 第二等的木部特征和水平变化在三 xerophytic 种被描述, Zygophyllum xanthoxylon, Nitraria tangutorum,到西方的中国的蒺藜科土著人的 Tetraena 蒙古人集成通信适配器。所有种类让明显的生长除了,包围边界在 T 有时不连续。蒙古人集成通信适配器和 Z xanthoxylum 戒指到 semi-ring-porosity;简单穿孔板;轮流出现内部容器 pitting;非有中隔的纤维;帕拉气管的汇合的轴的实质;螺旋状的变厚和异种细胞的光线。然而,容器安排和容器的量的特征是不同的。容器元素趋于在 T 更短、更狭窄、更经常。蒙古人集成通信适配器能比在几乎不是不同的另外的二种导致更大的传导性的安全。沿着光线的方向的容器元素长度和纤维长度的变化显示出不规则的趋势。在两纤维长度和容器元素长度在树之中和在内树有重要差别。而且,在到荒芜的环境的解剖特征和适应性之间的关系也被讨论。 展开更多
关键词 人工林 退化模型 地理信息系统 退化评价 半干旱区
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Experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering boundary effect
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作者 Xuwei Wang Yeshuang Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期1072-1084,共13页
The boundary condition is a crucial factor affecting the permeability variation due to suffusion.An experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundar... The boundary condition is a crucial factor affecting the permeability variation due to suffusion.An experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundary effect is conducted,where the hydraulic head difference(DH)varies,and the boundary includes non-loss and soil-loss conditions.Soil samples are filled into seven soil storerooms connected in turn.After evaluation,the variation in content of fine sand(ΔR_(f))and the hydraulic conductivity of soils in each storeroom(C_(i))are analyzed.In the non-loss test,the soil sample filling area is divided into runoff,transited,and accumulated areas according to the negative or positive ΔR_(f) values.ΔR_(f) increases from negative to positive along the seepage path,and Ci decreases from runoff area to transited area and then rebounds in accumulated area.In the soil-loss test,all soil sample filling areas belong to the runoff area,where the gentle-loss,strengthened-loss,and alleviated-loss parts are further divided.ΔR_(f) decreases from the gentle-loss part to the strengthened-loss part and then rebounds in the alleviated-loss part,and C_(i) increases and then decreases along the seepage path.The relationship between ΔR_(f) and Ci is different with the boundary condition.Ci exponentially decreases with ΔR_(f) in the non-loss test and increases with ΔR_(f) generally in the soil-loss test. 展开更多
关键词 Suffusion PERMEABILITY Experimental investigation Boundary effect Horizontal seepage
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Restraint effect of partition wall on the tunnel floor heave in layered rock mass
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作者 YANG Yunyun HUANG Da +2 位作者 ZHONG Zhu LIU Yang PENG Jianbing 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2462-2479,共18页
The presence of horizontal layered rocks in tunnel engineering significantly impacts the stability and strength of the surrounding rock mass,leading to floor heave in the tunnel.This study focused on preparing layered... The presence of horizontal layered rocks in tunnel engineering significantly impacts the stability and strength of the surrounding rock mass,leading to floor heave in the tunnel.This study focused on preparing layered specimens of rock-like material with varying thickness to investigate the failure behaviors of tunnel floors.The results indicate that thin-layered rock mass exhibits weak interlayer bonding,causing rock layers near the surface to buckle and break upwards when subjected to horizontal squeezing.With an increase in the layer thickness,a transition in failure mode occurs from upward buckling to shear failure along the plane,leading to a noticeable reduction in floor heave deformation.The primary cause of significant deformation in floor heave is upward buckling failure.To address this issue,the study proposes the installation of a partition wall in the middle of the floor to mitigate heave deformation of the rock layers.The results demonstrate that the partition wall has a considerable stabilizing effect on the floor,reducing the zone of buckling failure and minimizing floor heave deformation.It is crucial for the partition wall to be sufficiently high to prevent buckling failure and ensure stability.Through simulation calculations on an engineering example,it is confirmed that implementing a partition wall can effectively reduce floor heave and enhance the stability of tunnel floor. 展开更多
关键词 Layered rock Floor heave Horizontal compression test Failure behavior Partition wall
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INEOS聚丙烯装置大型卧式反应器用传动胀套设计探讨
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作者 任斌 周涛 +1 位作者 马凯旋 梁元月 《山东化工》 CAS 2024年第12期192-195,共4页
介绍了胀套结构在INEOS聚丙烯装置大型卧式反应器搅拌轴集装机械密封无键传动的应用,并根据传动特征及主要技术参数进行胀套扭矩传递计算与校核。旨在进一步理解该引进反应器核心结构和部件的设计思路与理念,保证关键核心部件使用过程... 介绍了胀套结构在INEOS聚丙烯装置大型卧式反应器搅拌轴集装机械密封无键传动的应用,并根据传动特征及主要技术参数进行胀套扭矩传递计算与校核。旨在进一步理解该引进反应器核心结构和部件的设计思路与理念,保证关键核心部件使用过程中各项参数、性能都满足装置长周期、安全生产要求。 展开更多
关键词 inEOS聚丙烯装置 卧式反应器 胀套结构
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Numerical Simulation of the Seismic Response of a Horizontal Storage Tank Based on a SPH-FEM Coupling Method
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作者 Peilei Yan Endong Guo +1 位作者 HouliWu Liangchao Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1655-1678,共24页
A coupled numerical calculation method combining smooth particle hydrodynamics(SPH)and the finite element method(FEM)was implemented to investigate the seismic response of horizontal storage tanks.Anumericalmodel of a... A coupled numerical calculation method combining smooth particle hydrodynamics(SPH)and the finite element method(FEM)was implemented to investigate the seismic response of horizontal storage tanks.Anumericalmodel of a horizontal storage tank featuring a free liquid surface under seismic action was constructed using the SPH–FEM coupling method.The stored liquid was discretized using SPH particles,while the tank and supports were discretized using the FEM.The interaction between the stored liquid and the tank was simulated by using the meshless particle contact method.Then,the numerical simulation results were compared and analyzed against seismic simulation shaking table test data to validate the method.Subsequently,a series of numerical models,considering different liquid storage volumes and seismic effects,were constructed to obtain time history data of base shear and top center displacement,which revealed the seismic performance of horizontal storage tanks.Numerical simulation results and experimental data showed good agreement,with an error rate of less than 18.85%.And this conformity signifies the rationality of the SPH-FEM coupling method.The base shear and top center displacement values obtained by the coupled SPH-FEM method were only 53.3% to 69.1% of those calculated by the equivalent mass method employed in the current code.As the stored liquid volume increased,the seismic response of the horizontal storage tank exhibited a gradual upward trend,with the seismic response increasing from 73% to 388% for every 35% increase in stored liquid volume.The maximum von Mises stress of the tank and the supports remained below the steel yield strength during the earthquake.The coupled SPH-FEM method holds certain advantages in studying the seismic problems of tanks with complex structural forms,particularly due to the representation of the flow field distribution during earthquakes by involving reservoir fluid participation. 展开更多
关键词 SPH-FEM coupling method horizontal storage tank seismic response SLOSHinG
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Single-station microtremor surveys for site characterization:A case study in Erzurum city,eastern Turkey
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作者 Fatih Karsli Erdem Bayrak 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期563-576,共14页
The single-station microtremor method is one of the fastest,most reliable,and cheapest methods used to identify dynamic soil properties.This study utilizes 49 single-station microtremor measurements to identify the dy... The single-station microtremor method is one of the fastest,most reliable,and cheapest methods used to identify dynamic soil properties.This study utilizes 49 single-station microtremor measurements to identify the dynamic soil properties of the Hilalkent quarter of the Yakutiye district in Erzurum.Soil dominant frequency and the amplification factor were calculated by using the Nakamura horizontal/vertical spectral ratio(H/V)method.While the soil dominant frequency values varied between 0.4 Hz and 10 Hz,the soil amplification factor changed between 1 and 10.Higher H/V values were acquired with lower frequency values.The vulnerability index(K_(g))and shear strain parameters that are utilized to estimate the damage that may be caused by an earthquake were mapped.Especially in the west side of the study area,higher K_(g) values were observed.The shear strain map was created with 0.25 g,0.50 g and 0.75 g bedrock accelerations,and soil types that lost elasticity during an earthquake were identified.The average shear wave velocity for the first 30 m(V_(s30))was calculated.Finally,it was observed that the western part of the study area,which resulted in a higher period and higher H/V,higher K_(g) and lower V_(s30) values,presents a higher risk of damage during an earthquake. 展开更多
关键词 Nakamura horizontal/vertical spectral ratio single-station microtremor predominant frequency vulnerability index Erzurum
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Productivity Prediction Model of Perforated Horizontal Well Based on Permeability Calculation in Near-Well High Permeability Reservoir Area
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作者 Shuangshuang Zhang Kangliang Guo +3 位作者 Xinchen Gao Haoran Yang Jinfeng Zhang Xing Han 《Energy Engineering》 EI 2024年第1期59-75,共17页
To improve the productivity of oil wells,perforation technology is usually used to improve the productivity of horizontal wells in oilfield exploitation.After the perforation operation,the perforation channel around t... To improve the productivity of oil wells,perforation technology is usually used to improve the productivity of horizontal wells in oilfield exploitation.After the perforation operation,the perforation channel around the wellbore will form a near-well high-permeability reservoir area with the penetration depth as the radius,that is,the formation has different permeability characteristics with the perforation depth as the dividing line.Generally,the permeability is measured by the permeability tester,but this approach has a high workload and limited application.In this paper,according to the reservoir characteristics of perforated horizontal wells,the reservoir is divided into two areas:the original reservoir area and the near-well high permeability reservoir area.Based on the theory of seepage mechanics and the formula of open hole productivity,the permeability calculation formula of near-well high permeability reservoir area with perforation parameters is deduced.According to the principle of seepage continuity,the seepage is regarded as the synthesis of two directions:the horizontal plane elliptic seepage field and the vertical plane radial seepage field,and the oil well productivity prediction model of the perforated horizontal well is established by partition.The model comparison demonstrates that the model is reasonable and feasible.To calculate and analyze the effect of oil well production and the law of influencing factors,actual production data of the oilfield are substituted into the oil well productivity formula.It can effectively guide the technical process design and effect prediction of perforated horizontal wells. 展开更多
关键词 Perforated horizontal well PERMEABILITY productivity model sensitivity analysis
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A Well Productivity Model for Multi-Layered Marine and Continental Transitional Reservoirs with Complex Fracture Networks
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作者 Huiyan Zhao Xuezhong Chen +3 位作者 Zhijian Hu Man Chen Bo Xiong Jianying Yang 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1313-1330,共18页
Using the typical characteristics of multi-layered marine and continental transitional gas reservoirs as a basis,a model is developed to predict the related well production rate.This model relies on the fractal theory... Using the typical characteristics of multi-layered marine and continental transitional gas reservoirs as a basis,a model is developed to predict the related well production rate.This model relies on the fractal theory of tortuous capillary bundles and can take into account multiple gas flow mechanisms at the micrometer and nanometer scales,as well as the flow characteristics in different types of thin layers(tight sandstone gas,shale gas,and coalbed gas).Moreover,a source-sink function concept and a pressure drop superposition principle are utilized to introduce a coupled flow model in the reservoir.A semi-analytical solution for the production rate is obtained using a matrix iteration method.A specific well is selected for fitting dynamic production data,and the calculation results show that the tight sandstone has the highest gas production per unit thickness compared with the other types of reservoirs.Moreover,desorption and diffusion of coalbed gas and shale gas can significantly contribute to gas production,and the daily production of these two gases decreases rapidly with decreasing reservoir pressure.Interestingly,the gas production from fractures exhibits an approximately U-shaped distribution,indicating the need to optimize the spacing between clusters during hydraulic fracturing to reduce the area of overlapping fracture control.The coal matrix water saturation significantly affects the coalbed gas production,with higher water saturation leading to lower production. 展开更多
关键词 Marine-continental transitional reservoir multi-layered reservoir seepage mechanisms apparent permeability hydraulic horizontal well productivity model
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Influences of clean fracturing fluid viscosity and horizontal in-situ stress difference on hydraulic fracture propagation and morphology in coal seam
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作者 Gang Wang Shuxin Wang +5 位作者 Yixin Liu Qiming Huang Shengpeng Li Shuliang Xie Jinye Zheng Jiuyuan Fan 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期159-175,共17页
The viscosity of fracturing fluid and in-situ stress difference are the two important factors that affect the hydraulic fracturing pressure and propagation morphology. In this study, raw coal was used to prepare coal ... The viscosity of fracturing fluid and in-situ stress difference are the two important factors that affect the hydraulic fracturing pressure and propagation morphology. In this study, raw coal was used to prepare coal samples for experiments, and clean fracturing fluid samples were prepared using CTAB surfactant. A series of hydraulic fracturing tests were conducted with an in-house developed triaxial hydraulic fracturing simulator and the fracturing process was monitored with an acoustic emission instrument to analyze the influences of fracturing fluid viscosity and horizontal in-situ stress difference on coal fracture propagation. The results show that the number of branched fractures decreased, the fracture pattern became simpler, the fractures width increased obviously, and the distribution of AE event points was concentrated with the increase of the fracturing fluid viscosity or the horizontal in-situ stress difference. The acoustic emission energy decreases with the increase of fracturing fluid viscosity and increases with the increase of horizontal in situ stress difference. The low viscosity clean fracturing fluid has strong elasticity and is easy to be compressed into the tip of fractures, resulting in complex fractures. The high viscosity clean fracturing fluids are the opposite. Our experimental results provide a reference and scientific basis for the design and optimization of field hydraulic fracturing parameters. 展开更多
关键词 Clean fracturing fluid Hydraulic fracturing VISCOSITY Horizontal in-situ stress difference Hydraulic fracture morphology Acoustic emission
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Deterministic and probabilistic analysis of great-depth braced excavations:A 32 m excavation case study in Paris
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作者 Tingting Zhang Julien Baroth +1 位作者 Daniel Dias Khadija Nejjar 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1505-1521,共17页
The Fort d’Issy-Vanves-Clamart(FIVC)braced excavation in France is analyzed to provide insights into the geotechnical serviceability assessment of excavations at great depth within deterministic and probabilistic fra... The Fort d’Issy-Vanves-Clamart(FIVC)braced excavation in France is analyzed to provide insights into the geotechnical serviceability assessment of excavations at great depth within deterministic and probabilistic frameworks.The FIVC excavation is excavated at 32 m below the ground surface in Parisian sedimentary basin and a plane-strain finite element analysis is implemented to examine the wall deflections and ground surface settlements.A stochastic finite element method based on the polynomial chaos Kriging metamodel(MSFEM)is then proposed for the probabilistic analyses.Comparisons with field measurements and former studies are carried out.Several academic cases are then conducted to investigate the great-depth excavation stability regarding the maximum horizontal wall deflection and maximum ground surface settlement.The results indicate that the proposed MSFEM is effective for probabilistic analyses and can provide useful insights for the excavation design and construction.A sensitivity analysis for seven considered random parameters is then implemented.The soil friction angle at the excavation bottom layer is the most significant one for design.The soil-wall interaction effects on the excavation stability are also given. 展开更多
关键词 Braced deep excavation Soil-wall interaction Stochastic finite element method Horizontal wall deflection SETTLEMENT Failure probability
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Wellbore Cleaning Degree and Hydraulic Extension in Shale Oil Horizontal Wells
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作者 Xin Ai Mian Chen 《Fluid Dynamics & Materials Processing》 EI 2024年第3期661-670,共10页
The efficient development and exploitation of shale oil depends on long-distance horizontal wells. As the degreeof cleaning of the wellbore plays a key role in these processes, in this study, this problem is investiga... The efficient development and exploitation of shale oil depends on long-distance horizontal wells. As the degreeof cleaning of the wellbore plays a key role in these processes, in this study, this problem is investigated experimentallyby focusing on the dimensionless cuttings bed height. A method is proposed to calculate the horizontalwellhydraulic extension taking into account the influence of the wellbore cleaning degree on the wellborepressure distribution and assess the effect of a variety of factors such as the bottom hole pressure, the circulatingpressure drop, the drilling pump performance and the formation properties. The analysis shows that the hydraulicextension of horizontal wells decreases with an increase in the cuttings bed height, and the higher the displacementof drilling fluid, the faster the hydraulic extension declines. The annular pressure drop of the horizontalsection increases with the increase of the cuttings bed height, resulting in a higher bottom-hole pressure. Severalarguments are provided to guide the safe drilling of shale oil horizontal wells and overcome the limits of currenttechnological approaches. 展开更多
关键词 Shale oil horizontal well hydraulic extension wellbore cleaning degree pressure distribution mechanism analysis
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