检索结果-南通市图书馆

The influences of perforating phase and bedding planes on the fracture deflection in laminated shale

Petroleum Science 2024年第2期21卷 1221-1230页

作者： Ming-Zhe Gu Mao sheng Xiao-Ying Zhuang Xin-Yi Li Gen-sheng Li National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China College of Petroleum Engineering China University of PetroleumBeijing102249China College of Civil Engineering Tongji UniversityShanghai200092China

The perforating phase leads to complex and diverse hydraulic fracture propagation behaviors in laminated shale formations. In this paper, a 2D high-speed imaging scheme which can capture the interaction between perforating phase and natural shale bedding planes was proposed. The phase field method was used to simulate the same conditions as in the experiment for verification and hydraulic fracture propagation mechanism under the competition of perforating phase and bedding planes was *** results indicate that the bedding planes appear to be no influence on fracture propagation while the perforating phase is perpendicular to the bedding planes, and the fracture propagates along the perforating phase without deflection. When the perforating phase algins with the bedding planes, the fracture initiation pressure reserves the lowest value, and no deflection occurs during fracture propagation. When the perforating phase is the angle 45°, 60°and 75°of bedding planes, the bedding planes begin to play a key role on the fracture deflection. The maximum deflection degree is reached at the perforating phase of75°. Numerical simulation provides evidence that the existence of shale bedding planes is not exactly equivalent to anisotropy for fracture propagation and the difference of mechanical properties between different shale layers is the fundamental reason for fracture deflection. The findings help to understand the intrinsic characteristics of shale and provide a theoretical basis for the optimization design of field perforation parameters.

关键词： Shale Propagation Perforating Bedding Structure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Recent advances in promising drugs for primary prevention of gastroesophageal variceal bleeding with cirrhotic portal hypertension

引用

Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 4-13页

作者： Ji-Yao sheng Zi-Fan Meng Qiao Li Yong-sheng Yang Department of Hepatobiliary and Pancreatic Surgery the Second Hospital of Jilin UniversityChangchun 130041China Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases the Second Hospital of Jilin UniversityChangchun 130041China

Background:Gastroesophageal variceal bleeding is one of the most severe complications of patients with *** primary prevention drugs,including non-selectiveβ-blockers,have effectively reduced the incidence of bleeding,their efficacy is limited due to side effects and related *** recent advances in precision medicine,precise drug treatment provides better treatment *** sources:Literature search was conducted in PubMed,MEDLINE and Web of Science for relevant articles published up to May *** on clinical trials was obtained from https://***/and http://***/.Results:The in-depth understanding of the pathogenesis and advances of portal hypertension has enabled the discovery of multiple molecular targets for promising *** to the site of action,these drugs could be classified into four classes:intrahepatic,extrahepatic,both intrahepatic and extrahepatic targets and *** these classes of drugs offer advantages over traditional treatments in prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal ***:This review classified and summarized the promising drugs,which prevent gastroesophageal variceal bleeding by targeting specific markers of pathogenesis of portal hypertension,demonstrating the significance of using the precision medicine strategy to discover and develop promising drugs for the primary prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

关键词： Cirrhotic portal hypertension Target drug Primary prevention Bleeding

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Feedback processing in the primate brain and in AI systems

引用

Science China(Technological Sciences) 2024年第8期67卷 2297-2309页

作者： JIANG Yong HE sheng Institute of Biophysics Chinese Academy of SciencesBeijing 100101China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China University of Chinese Academy of Sciences Beijing 100049China

The primate brain and artificial intelligence(AI) can both be conceptualized as information processing systems, each with its own distinct biological and computational architectures. While there are parallels between them, their respective structural and functional connections show significant differences. In this paper, we examine the central role of feedback processing in both the primate brain and AI systems, which has been shown to be crucial in shaping neural processing. By reviewing the key features of feedback processes in the primate brain, which allows the brain to incorporate prior knowledge, contextual information, and taskdemands into early-stage processing, we highlight the divergence in goals and functions between biological and AI *** these differences is crucial for elucidating the cognitive capabilities of the primate brain and for addressing computational challenges in AI. In advocating “Cognition-Inspired-Computation”, we suggest that integrating insights from feedback processing in the primate brain into AI research will offer potentially significant improvements for the advancement of AI systems.

关键词： cognitive neuroscience artificial intelligence feedback processing attention learning

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Demonstration of high-dimensional controlled quantum teleportation for the first time

引用

Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 163-164页

作者： Yu-Bo sheng Lan Zhou College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China College of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China

Controlled quantum teleportation(CQT) [1] is the tripartite version of quantum teleportation and it allows the teleportation of an unknown quantum state under the control of a third party. Compared with low-dimensional counterparts,high-dimensional CQT can exhibit larger information transmission capacity and a higher control power [2,3].

关键词： quantum dimensional high

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Disorders of cardiac rhythm in China

引用

Journal of Geriatric Cardiology 2024年第7期21卷 703-712页

作者： sheng-Shou HU The Writing Committee of the Report on Cardiovascular Health and Diseases in China

The Annual Report on Cardiovascular Health and Diseases in China(2022)intricate landscape of cardiovascular health in *** connection with the previous section,this seventh section of the report offers a comprehensive analysis of dis-orders of heart rhythm in *** 2021,China has achieved significant development and gratifying results in many aspects of the field of *** bundle branch pacing(LBBP),as an emerging pacing technique originating from China,has received widespread *** research results have emerged on its indications,surgical procedures,clinical evaluation,and com-parison with other pacing *** feasibility,effectiveness,and safety have been basically verified,but its long-term pro-gnosis still needs further confirmation from larger samples and longer follow-up time research *** pacemakers have begun to be used in a wider range of clinical applications,and related large sample cohort studies have been *** addi-tion,there are also noteworthy new achievements in the fields of pacemaker remote programming,anticoagulation and radiofre-quency catheter ablation(RFCA)therapy for atrial fibrillation,and implantable cardioverter defibrillator prevention of sudden cardiac *** terms of clinical practice,due to COVID-19 pandemic,the number of RFCA procedures and other device im-plantations in China has fluctuated,but it has gradually recovered since 2020.

关键词： cardiac prevention landscape

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

激光雷达反演边界层高度方法评估及其在北京的应用

引用

大气科学 2018年第2期42卷 435-446页

作者：李霞权建农王飞盛久江高扬赵德龙程志刚北京市人工影响天气办公室北京100089 云降水物理研究和云水资源开发北京市重点实验室北京100089 中国气象局北京城市气象研究所北京100089 中国气象科学研究院中国气象局人工影响天气中心北京100081

边界层高度是影响大气边界层发展和空气污染程度的重要因子,是环境和气候研究的重要参数。本文利用激光雷达对北京地区2011年5月至2012年4月的边界层高度进行探测分析,采用小波协方差方法反演边界层高度,评估了该方法的适用性。得到基... 详细信息

边界层高度是影响大气边界层发展和空气污染程度的重要因子,是环境和气候研究的重要参数。本文利用激光雷达对北京地区2011年5月至2012年4月的边界层高度进行探测分析,采用小波协方差方法反演边界层高度,评估了该方法的适用性。得到基于小波协方差方法自动判断边界层高度的最优参数组合,激光雷达与飞机探测结果对比一致性较好;与探空结果相关系数0.88,激光雷达反演的边界层高度略偏高。当激光雷达的垂直分辨率为30 m时,更加适合北京地区的步长和阈值分别为210 m和0.05;当激光雷达的垂直分辨率为15 m时,步长和阈值分别为135 m和0.05。分析期间,不同季节边界层高度日变化有明显的不同,夏季14:00(北京时)左右达到最高,较高的边界层高度可维持3~4 h,平均可达1.30 km;冬季较高边界层高度只能维持2 h左右,平均为1.08 km。有云与无云天气边界层日变化特征以及边界层高度存在显著的差异,云的存在减少了到达地面的直接辐射,抑制了湍流的发展,进一步抑制了边界层的发展;本文也将激光雷达反演边界层高度结果应用于观测时期边界层高度与地面污染的关系研究中,统计得到边界层高度与PM2.5浓度的相关系数为-0.340。

关键词：边界层高度小波协方差方法激光雷达飞机探空

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Energy flux and waveform of gravitational wave generated by coalescing slow-spinning binary system in effective one-body theory

引用

Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 73-83页

作者： Weike Deng sheng Long Jiliang Jing Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Educationand Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

We extend our research on the energy flux and waveform characteristics of gravitational waves generated by merging nonspinning binary black holes through self-consistent effective one-body theory to include binary systems with slowly spinning black ***,we decompose the equation for the null tetrad component of the gravitationally perturbed Weyl tensorψ_4~B into radial and angular parts,leveraging the second-order approximation of the rotation parameter ***,we derive an analytical solution for the radial equation and observe that our results are contingent upon the parameters a_(2),a_(3),and a,which represent the second-and third-order correction parameters,***,we calculate the energy flux,the radiation-reaction force and the waveform for the“plus”and“cross”modes of the gravitational waves generated by merging slowly spinning binary black holes.

关键词： post-Minkowskian approximation effective-one-body theory gravitational waveform template

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Energy flux and waveforms by coalescing spinless binary system in effective one-body theory

引用

Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 58-68页

作者： sheng Long Weike Deng Jiliang Jing Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationSynergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

We present a study on the energy radiation rate and waveforms of the gravitational wave generated by coalescing spinless binary systems up to the third post-Minkowskian approximation in the effective one-body *** derive an analytical expansion of the null tetrad components of the gravitational perturbed Weyl tensorΨ4in the effective spacetime,we utilize the method proposed by Sasaki et *** this investigation,we discover more general integral formulas that provide a theoretical framework for computing the results in any ***,we successfully compute the energy radiation rate and waveforms of the gravitational wave,which include the results of the Schwarzschild case and the correction terms resulting from the dimensionless parameters a2and a3in the effective metric.

关键词： post-Minkowskian approximation effective one-body theory gravitational waveform template

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Exploration of Strong Metal-Support Interaction in Heterogeneous Catalysts by in situ Transmission Electron Microscopy

引用

Chinese Journal of Chemistry 2024年第9期42卷 1004-1008页

作者： Yongjun Jiang sheng Dai Key Laboratoryfor Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry&Molecular EngineeringEast China Universityof Science and TechnologyShanghai 200237China

The phenomenon of strong metal-support interaction(SMSI)observed in supported metal catalysts,usually accompanied by the formation of the encapsulation layer on metal nanoparticles,has attracted extensive research attention due to its significance in heterogeneous ***,great progress has been made in recent years in investigating SMSI by in situ transmission electron microscopy(TEM),along with an enhanced comprehension of the underlying mechanisms governing SMSI *** emerging topic summarizes recent progress utilizing in situ TEM to study the interaction between metal and support and the relationship between the structure and performance of the supported catalyst under reaction conditions.A brief perspective about the use of in situ TEM for further study of SMSI is also presented,showing prospects in this field that will stimulate further upsurging research in promoting the catalytic efficiency of supported catalysts.

关键词： Heterogeneous catalysis In situ TEM Strong metal-support interaction Structure changes Interfaces Structural evolution

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Limits of Riemann Solutions for Isentropic MHD in a Variable Cross-Section Duct as Magnetic Field Vanishes

引用

Chinese Annals of Mathematics,Series B 2024年第4期45卷 637-660页

作者： Wancheng sheng Tao XIAO Department of Mathematics Shanghai University Shanghai Aircraft Design and Research Institute

The stability for magnetic field to the solution of the Riemann problem for the polytropic fluid in a variable cross-section duct is discussed. By the vanishing magnetic field method, the stable solutions are determined by comparing the limit solutions with the solutions of the Riemann problem for the polytropic fluid in a duct obtained by the entropy rate admissibility criterion.

关键词： 35L50 35L65 35L80 76J20 76N10 Magnetogasdynamics Riemann problem Stability Vanishing magnetic field method Variable duct

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：