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基于FD-QM的“财务会计理论与实务”线上线下课程建设研究
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作者 刘永丽 周浩东 穆品静 《管理工程师》 2024年第4期74-80,共7页
随着信息技术的迅速发展和教育模式的变革,如何有效提升研究生课程的教学质量和学习效果成为一个重要课题。文章以FD-QM标准为指导,以专硕研究生“财务会计理论与实务”课程为对象,遵循“一致性构建”原则,按照课程建设目标,将学习目标... 随着信息技术的迅速发展和教育模式的变革,如何有效提升研究生课程的教学质量和学习效果成为一个重要课题。文章以FD-QM标准为指导,以专硕研究生“财务会计理论与实务”课程为对象,遵循“一致性构建”原则,按照课程建设目标,将学习目标、学习活动、学业考核等进行线上和线下的有机融合,得出课程设计方案。方案经过实施发现,依据FD-QM标准进行课程设计,可降低设计者的主观性与盲目性对课程设计的影响,使得课程设计更为科学合理。遵循FD-QM标准中的“一致性构建原则”可以真正做到“以学生为中心”,让各类课程资源得到更有效地利用。以FD-QM标准为指导设计课程,在提高教学质量的同时,还会帮助课程设计者达成课程建设目标。 展开更多
关键词 FD-qm标准 财务会计理论与实务 线上线下
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Editorial for Multiscale&Multifield Coupling in Geomechanics
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作者 Min Wang Pengzhi Pan +1 位作者 Andrew H.C.Chan Y.T.Feng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1919-1921,共3页
We are delighted to serve as guest editors for this special issue in the Journal of Rock Mechanics and Geotechnical Engineering.The purpose of this special issue is dedicated to gathering the latest research work on M... We are delighted to serve as guest editors for this special issue in the Journal of Rock Mechanics and Geotechnical Engineering.The purpose of this special issue is dedicated to gathering the latest research work on Multiscale&Multifield Coupling in Geomechanics,where we delve into the intricate interplay of various fields and scales that govern the behavior of geomaterials.In total,30 manuscripts from USA,China,UK,Germany,Canada,India and United Arab Emirates are selected to be included in this issue. 展开更多
关键词 materials. GATHERING mechanics
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Induction System for a Fusion Reactor: Quantum Mechanics Chained up
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作者 Friedrich Björn Grimm 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期158-166,共9页
In the quest for a sustainable and abundant energy source, nuclear fusion technology stands as a beacon of hope. This study introduces a groundbreaking quantum mechanically effective induction system designed for magn... In the quest for a sustainable and abundant energy source, nuclear fusion technology stands as a beacon of hope. This study introduces a groundbreaking quantum mechanically effective induction system designed for magnetic plasma confinement within fusion reactors. The pursuit of clean energy, essential to combat climate change, hinges on the ability to harness nuclear fusion efficiently. Traditional approaches have faced challenges in plasma stability and energy efficiency. The novel induction system presented here not only addresses these issues but also transforms fusion reactors into integrated construction systems. This innovation promises compact fusion reactors, marking a significant step toward a clean and limitless energy future, free from the constraints of traditional power sources. This revolutionary quantum induction system redefines plasma confinement in fusion reactors, unlocking clean, compact, and efficient energy production. 展开更多
关键词 Fusion Reactor Plasma Confinement Quantum mechanics Clean Energy
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碱催化p-QMs的1,6-共轭加成合成二芳基甲基(硫)醚
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作者 罗金华 陈阳 +2 位作者 王欣 李蕾 王贺 《辽宁石油化工大学学报》 CAS 2024年第4期1-9,共9页
在摩尔分数为20%的氢氧化钠的催化作用下,实现了对亚甲基苯醌(p-QMs)与醇(或硫酚)的溶剂解反应,即p-QMs的1,6-共轭加成反应,以37%~95%的产率制备了一系列二芳基甲基(硫)醚类化合物。结果表明,该反应具有操作简便、反应条件温和高效、官... 在摩尔分数为20%的氢氧化钠的催化作用下,实现了对亚甲基苯醌(p-QMs)与醇(或硫酚)的溶剂解反应,即p-QMs的1,6-共轭加成反应,以37%~95%的产率制备了一系列二芳基甲基(硫)醚类化合物。结果表明,该反应具有操作简便、反应条件温和高效、官能团耐受性良好等特点;该方法易于放大,能以80%的产率得到二芳基甲基乙基醚,为后期的潜在应用与转化提供了可能。 展开更多
关键词 碱催化 对亚甲基苯醌 1 6-共轭加成 二芳基甲基醚
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Case study on the mechanics of NPR anchor cable compensation for large deformation tunnel in soft rock in the Transverse Mountain area,China
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作者 LI Yong ZHENG Jing +3 位作者 HUO Shu-sen WANG Feng-nian HE Man-chao TAO Zhi-gang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2054-2069,共16页
A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced duri... A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced during the tunnel construction.To mitigate this problem,a support system was designed incorporating negative Poisson ratio(NPR)anchor cables with negative Poisson ratio effect.Physical model experiments,field experiments,and numerical simulation experiments were conducted to investigate the compensation mechanical behavior of NPR anchor cables.The large deformations of soft rocks in the Daliangshan Tunnel are caused by a high ground stress,a high degree of joint fracture development,and a high degree of surrounding rock fragmentation.A compensation mechanics support system combining long and short NPR anchor cables was suggested to provide sufficient counter-support force(approximately 350 kN)for the surrounding rock inside the tunnel.Comparing the NPR anchor cable support system with the original support system used in the Daliangshan tunnel showed that an NPR anchor cable support system,combining cables of 6.3 m and 10.3 m in length,effectively prevented convergence of surrounding rock deformation,and the integrated settlement convergence value remained below 300 mm.This study provides an effective scientific basis for resolving large deformation problems in deeply buried soft rocks in western transverse mountain areas. 展开更多
关键词 soft rock large deformation NPR anchor cable physical model numerical simulation compensation mechanics
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Characteristics of Rock Mechanics Response and Energy Evolution Regime of Deep Reservoirs in the Bozhong Sag,Bohai Bay Basin
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作者 Suogui Shang Kechao Gao +4 位作者 QingbinWang Xinghua Zhang Pengli Zhou Jianhua Li Peng Chu 《Energy Engineering》 EI 2024年第9期2505-2524,共20页
Hydraulic fracturing is a mature and effectivemethod for deep oil and gas production,which provides a foundation for deep oil and gas production.One of the key aspects of implementing hydraulic fracturing technology l... Hydraulic fracturing is a mature and effectivemethod for deep oil and gas production,which provides a foundation for deep oil and gas production.One of the key aspects of implementing hydraulic fracturing technology lies in understanding mechanics response characteristics of rocks in deep reservoirs under complex stress conditions.In this work,based on outcrop core samples,high-stress triaxial compression tests were designed to simulate the rock mechanics behavior of deep reservoirs in Bozhong Sag.Additionally,this study analyzes the deformation and damage law for rock under different stress conditions.Wherein,with a particular focus on combining energy dissipation theory to further understand damage law for deep reservoirs.The experimental results show that regardless of stress conditions,the process of deformation/failure of deep-seated reservoirs goes through five stages:Fracture compaction,newfracture formation,stable fracture expansion,unstable fracture expansion,and post-peak residual deformation.Under different stress conditions,the energy change laws of specimens are similar.The energy dissipation process of rocks corresponds closely to the trend of deformation-failure curve,then displays distinctive stage characteristics.Wherein,in stage of rock fracture compaction,the input energy curve is approximately coincident with the elastic strain energy curve,while the dissipation energy curve remains near zero.With the increase of strain,the growth rate of elastic strain energy increases gradually,but with the deformation entering the crack propagation stage,the growth rate of elastic strain energy slows down and the dissipation energy increases gradually.Finally,in the post-peak stage,rock fracture releases a lot of energy,which leads to the sharp decline of elastic strain energy curve.In addition,the introduction of damage variable D quantifies the analysis of the extent of failure for rocks.During the process of increasing strain,rock damage exhibits nonlinear growth with increasing stress. 展开更多
关键词 Deep rock mechanics triaxial compression energy dissipation damage variable
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Dental Treatment Using Quantum Mechanics for Knee Joint Pain
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作者 Yoshiro Fujii 《Natural Science》 2024年第9期146-149,共4页
In clinical practice, dentists sometimes encounter phenomena that cannot be explained by modern western medical concepts;for example, the patient’s medical symptoms improve by bringing medicines or dentures close to ... In clinical practice, dentists sometimes encounter phenomena that cannot be explained by modern western medical concepts;for example, the patient’s medical symptoms improve by bringing medicines or dentures close to the body. Although it seems difficult to completely elucidate the mechanism through modern western medicine, it can be explained using quantum mechanics. The quantum, the smallest unit of matter composition, exhibits wave-particle duality. The fact that symptoms can be improved simply by bringing dentures or medicines closer to the body indicates that the waves emitted by dentures or medicines interfere with the pathological waves emitted by the pathological site. Thus, the pathological waves are deformed and lead to a change in symptoms. In this way, quantum theory can explain phenomena that are difficult to elucidate in conventional medicine, which are encountered in clinical practice. So far, the author has presented a case of difficulty in raising the upper limb where the symptoms improved without the need for dentures in the mouth by adjusting the dentures outside the mouth. This time, the author would like to introduce a case which the patient’s knee pain improved by adjusting the dentures outside the mouth. 展开更多
关键词 Denture Adjustment Knee Joint Pain Quantum mechanics Wave Interference The Bi-Digital O-Ring Test
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New Approach to Synchronize General Relativity and Quantum Mechanics with Constant “K”-Resulting Dark Matter as a New Fundamental Force Particle
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作者 Siva Prasad Kodukula 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期292-302,共11页
Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction a... Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction and expansion forces of space time. According to this, the space time with Planck diameter is a flat space time. This is the only diameter of space time that can be used as signal transformation in special relativity. This space time diameter defines the fundamental force which belongs to that space time. In quantum mechanics, this space time diameter is only the quantum of space which belongs to that particular fundamental force. Einstein’s general relativity equation and Planck parameters of quantum mechanics have been written in terms of equations containing a constant “K”, thus found a new equation for transformation of general relativity space time in to quantum space time. In this process of synchronization, there is a possibility of a new fundamental force between electromagnetic and gravitational forces with Planck length as its space time diameter. It is proposed that dark matter is that fundamental force carrying particle. By grand unification equation with space-time diameter, we found a coupling constant as per standard model “α<sub>s</sub>” for that fundamental force is 1.08 × 10<sup>-23</sup>. Its energy calculated as 113 MeV. A group of experimental scientists reported the energy of dark matter particle as 17 MeV. Thorough review may advance science further. 展开更多
关键词 General Relativity Quantum mechanics Space Time Dark Matter A New Fundamental Constant “K”
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An 8-Node Plane Hybrid Element for StructuralMechanics Problems Based on the Hellinger-Reissner Variational Principle
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作者 Haonan Li WeiWang +1 位作者 Quan Shen Linquan Yao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1277-1299,共23页
The finite element method (FEM) plays a valuable role in computer modeling and is beneficial to the mechanicaldesign of various structural parts. However, the elements produced by conventional FEM are easily inaccurat... The finite element method (FEM) plays a valuable role in computer modeling and is beneficial to the mechanicaldesign of various structural parts. However, the elements produced by conventional FEM are easily inaccurate andunstable when applied. Therefore, developing new elements within the framework of the generalized variationalprinciple is of great significance. In this paper, an 8-node plane hybrid finite element with 15 parameters (PHQ8-15β) is developed for structural mechanics problems based on the Hellinger-Reissner variational principle.According to the design principle of Pian, 15 unknown parameters are adopted in the selection of stress modes toavoid the zero energy modes.Meanwhile, the stress functions within each element satisfy both the equilibrium andthe compatibility relations of plane stress problems. Subsequently, numerical examples are presented to illustrate theeffectiveness and robustness of the proposed finite element. Numerical results show that various common lockingbehaviors of plane elements can be overcome. The PH-Q8-15β element has excellent performance in all benchmarkproblems, especially for structures with varying cross sections. Furthermore, in bending problems, the reasonablemesh shape of the new element for curved edge structures is analyzed in detail, which can be a useful means toimprove numerical accuracy. 展开更多
关键词 8-node plane hybrid element Hellinger-Reissner variational principle locking behaviors structural mechanics problems
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基于OBE理念及FD-QM标准的线上线下混合式教学法在《医学免疫学》课程教学中的应用
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作者 孙合强 王坤 邓新立 《标记免疫分析与临床》 CAS 2024年第3期574-578,共5页
高等教育是科技第一生产力、创新第一动力、人才第一资源的重要结合点,特别是医学高等教育人才培养质量,关乎着民生健康和社会进步。然而,大部分高校《医学免疫学》教学模式仍是“填鸭式”教学,学生培养质量不令人满意。因此,探索有效... 高等教育是科技第一生产力、创新第一动力、人才第一资源的重要结合点,特别是医学高等教育人才培养质量,关乎着民生健康和社会进步。然而,大部分高校《医学免疫学》教学模式仍是“填鸭式”教学,学生培养质量不令人满意。因此,探索有效提高高等教育《医学免疫学》教学模式意义重大。本研究通过聚焦国内外先进教学理念和方法,基于OBE教育理念和FD-QW课程质量标准,充分结合线上线下课程资源,开展混合式教学模式在医学本科专业基础课程《医学免疫学》中的应用,并开展随机对照试验,对比传统教学组与混合式教学组的教学质量效果差异,探究科学、高效的新型高等教育人才培养模式。通过实践,混合式教学组的教学质量效果整体明显好于传统教学组。5大实施路径,可为高等教育《医学免疫学》教学模式提供参考性建议。 展开更多
关键词 OBE教育理念 FD-qm标准 线上线下混合式“金课” 医学免疫学 教学模式
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Improved Units of Measure in Rotational Mechanics
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作者 Richard James Petti 《World Journal of Mechanics》 2024年第1期1-7,共7页
The SI system of units in rotational mechanics yields correct numerical results, but it produces physically incorrect units of measure in many cases. SI units also violate the principle of general covariance—the gene... The SI system of units in rotational mechanics yields correct numerical results, but it produces physically incorrect units of measure in many cases. SI units also violate the principle of general covariance—the general rule for defining continuous coordinates and units in mathematics and mathematical physics. After 30+ years of wrestling with these problems, the ultimate authority on units of measure has declared that Newton–meter and Joule are not equivalent in rotational mechanics, as they are in the rest of physics. This article proposes a simple modification to SI units called “Nonstandard International units” (“NI units”) until a better name is agreed upon. NI units yield correct numerical results and physically correct units of measure, and they satisfy the principle of general covariance. The main obstacle to the adoption of NI units is the consensus among users that the radius of rotation should have the unit meter because the radius can be measured with a ruler. NI units assigned to radius should have units meter/radian because the radius is a conversion factor between angular size and circumferential length, as in arclength = rθ. To manage the social consensus behind SI units, the author recommends retaining SI units as they are, and informing users who want correct units that NI units solve the technical problems of SI units. 展开更多
关键词 Rotational mechanics Angular Unit TORQUE Moment of Inertia Angular Momentum General Covariance
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Investigation of the Micro-Mechanics of an Extruded Precipitation-Strengthened Magnesium Alloy under Cyclic Loading
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作者 Chuhao Liu Xiaodan Zhang +1 位作者 Huamiao Wang Yinghong Peng 《Journal of Materials Science and Chemical Engineering》 2024年第7期40-52,共13页
Precipitation strengthening is a crucial microscopic mechanism for enhancing the strength of magnesium alloys. In order to elucidate the influence of precipitation on the microscopic deformation mechanisms and macrosc... Precipitation strengthening is a crucial microscopic mechanism for enhancing the strength of magnesium alloys. In order to elucidate the influence of precipitation on the microscopic deformation mechanisms and macroscopic mechanical response of magnesium alloys under cyclic loading conditions, we employed a crystal plasticity model to analyze the stress-strain curves, specific crystal plane diffraction intensities, and the temporal evolution of various microscopic deformation mechanisms and twinning volume fractions for an extruded magnesium alloy, AXM10304, containing coherent precipitates. The research findings indicate that precipitation does not fundamentally alter the microscopic mechanisms of this alloy. However, it hinders twinning during the compression stage, mildly promotes detwinning during the tension stage, and enhances tension secondary hardening by elevating the difficulty of activation of the prismatic slip. 展开更多
关键词 Cyclic Deformation Magnesium Alloy In-Situ Neutron Diffraction Precipitation Strengthening Crystal Plasticity Lattice Strain Mechanism Evolution
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Teaching Experiment in Engineering Mechanics Based on Simulation Technology:A Case Study
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作者 Jinru Ma 《Journal of Contemporary Educational Research》 2024年第7期277-282,共6页
This paper explores the integration of simulation technology in Engineering Mechanics(EM)teaching in vocational colleges.A case study was conducted using the tensile test as an example,and digital resources,such as co... This paper explores the integration of simulation technology in Engineering Mechanics(EM)teaching in vocational colleges.A case study was conducted using the tensile test as an example,and digital resources,such as colored Mises stress nephograms,were obtained.These resources were integrated into the original curriculum to conduct teaching experiments.The results show that the use of digital resources significantly improved the quality of teaching in EM.The integration of simulation technology in EM teaching provides a promising direction for the improvement of vocational education and the cultivation of high-quality skilled talents.The development and application of more simulation-based teaching cases should be studied by scholars. 展开更多
关键词 Engineering mechanics Simulation technology Teaching experiment TEACHING Vocational education
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Research on the Assessment System of Computational Mechanics Courses Based on the TOPSIS Entropy Weight Model
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作者 Huijun Ning Ruhuan Yu +1 位作者 Qianshu Wang Mingming Lin 《Journal of Contemporary Educational Research》 2024年第6期166-182,共17页
This paper takes the assessment and evaluation of computational mechanics course as the background,and constructs a diversified course evaluation system that is student-centered and integrates both quantitative and qu... This paper takes the assessment and evaluation of computational mechanics course as the background,and constructs a diversified course evaluation system that is student-centered and integrates both quantitative and qualitative evaluation methods.The system not only pays attention to students’practical operation and theoretical knowledge mastery but also puts special emphasis on the cultivation of students’innovative abilities.In order to realize a comprehensive and objective evaluation,the assessment and evaluation method of the entropy weight model combining TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)multi-attribute decision analysis and entropy weight theory is adopted,and its validity and practicability are verified through example analysis.This method can not only comprehensively and objectively evaluate students’learning outcomes,but also provide a scientific decision-making basis for curriculum teaching reform.The implementation of this diversified course evaluation system can better reflect the comprehensive ability of students and promote the continuous improvement of teaching quality. 展开更多
关键词 TOPSIS entropy weight model Computational mechanics Course assessment and evaluation system Assessment model
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基于全面质量管理(TQM)视角的机电安装工程项目服务质量研究
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作者 戴宏杰 《中国高新科技》 2024年第8期95-97,100,共4页
“高质量发展”成为“新基建建设”的主旋律,与建筑业和制造业息息相关的机电安装工程即将迎来新的发展契机和挑战,亟需建立机电工程项目服务质量评价体系来规范行业标准。文章基于全面质量管理理论和SERVQUAL模型,从计划、实施、检查... “高质量发展”成为“新基建建设”的主旋律,与建筑业和制造业息息相关的机电安装工程即将迎来新的发展契机和挑战,亟需建立机电工程项目服务质量评价体系来规范行业标准。文章基于全面质量管理理论和SERVQUAL模型,从计划、实施、检查、总结处理4个阶段梳理建立机电安装工程项目服务质量评价指标体系,并提出4点提升机电安装工程项目全流程服务质量的对策,分别为统领设计全面质量管理系统、建设智能化项目管理系统、构建多元化考核评价体系和完善售后服务管理体系。 展开更多
关键词 机电安装工程项目 服务质量评价 SERVQUAL模型 TMQ PDCA循环
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基于FD-QM标准的在线病理学实验课程重构与实践 被引量:2
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作者 张东芳 张以忠 +2 位作者 赵东海 赵贵芳 钟秀宏 《中国医学教育技术》 2023年第2期222-228,共7页
教育信息化背景下,在线课程的建设与应用是实现人才培养目标的重要途径。为了加强应用型医学人才培养,全面提高人才培养质量,吉林医药学院病理学教研室对标FD-QM高等教育在线课程质量标准,聚焦“课程活动和学生互动”核心指标,在原有“... 教育信息化背景下,在线课程的建设与应用是实现人才培养目标的重要途径。为了加强应用型医学人才培养,全面提高人才培养质量,吉林医药学院病理学教研室对标FD-QM高等教育在线课程质量标准,聚焦“课程活动和学生互动”核心指标,在原有“病理学”实验线上课程基础上对实验在线课程进行重构,不仅为教师提供了在线课程建设实施依据,而且有效对接了新医科建设对医学人才培养的要求,教学效果满意。 展开更多
关键词 新医科 FD-qm标准 在线课程 病理学实验
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A generalized nonlinear three-dimensional failure criterion based on fracture mechanics 被引量:2
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作者 Zhaofeng Wang Pengzhi Pan +1 位作者 Jianping Zuo Yaohui Gao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第3期630-640,共11页
Based on fracture mechanics theory and wing crack model,a three-dimensional strength criterion for hard rock was developed in detail in this paper.Although the basic expression is derived from initiation and propagati... Based on fracture mechanics theory and wing crack model,a three-dimensional strength criterion for hard rock was developed in detail in this paper.Although the basic expression is derived from initiation and propagation of a single crack,it can be extended to microcrack cluster so as to reflect the macroscopic failure characteristic.Besides,it can be derived as HoekeBrown criterion when the intermediate principal stress σ_(2) is equal to the minimum principal stress σ_(3)(Zuo et al.,2015).In addition,the opening direction of the microcrack cluster decreases with the increase of the intermediate principal stress coefficient,which could be described by an empirical function and verified by 10 kinds of hard rocks.Rock strength is influenced by the coupled effect of stress level and the opening direction of the microcrack clusters related to the stress level.As the effects of these two factors on the strength are opposite,the intermediate principal stress effect is induced. 展开更多
关键词 Intermediate principal stress effect Rock strength Fracture mechanics True triaxial compression
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Application and prospects of 3D printing in physical experiments of rock mass mechanics and engineering:materials,methodologies and models 被引量:2
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作者 Qingjia Niu Lishuai Jiang +3 位作者 Chunang Li Yang Zhao Qingbiao Wang Anying Yuan 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第1期1-17,共17页
The existence of joints or other kinds of discontinuities has a dramatic efect on the stability of rock excavations and engineering.As a result,a great challenge in rock mass mechanics testing is to prepare rock or ro... The existence of joints or other kinds of discontinuities has a dramatic efect on the stability of rock excavations and engineering.As a result,a great challenge in rock mass mechanics testing is to prepare rock or rock-like samples with defects.In recent years,3D printing technology has become a promising tool in the feld of rock mass mechanics and engineering.This study frst reviews and discusses the research status of traditional test methods in rock mass mechanics tests of making rock samples with defects.Then,based on the comprehensive analysis of previous research,the application of 3D printing technology in rock mass mechanics is expounded from the following three aspects.The frst is the printing material.Although there are many materials for 3D printing,it has been found that 3D printing materials that can be used for rock mass mechanics research are very limited.After research,we summarize and evaluate printing material that can be used for rock mass mechanics studies.The second is the printing methodology,which mainly introduces the current application forms of 3D printing technology in rock mass mechanics.This includes printed precise casting molds and one-time printed samples.The last one is the printing model,which includes small-scale samples for mechanical tests and large-scale physical models.Then,the benefts and drawbacks of using 3D printing samples in mechanical tests and the validity of their simulation of real rock are discussed.Compared with traditional rock samples collected in nature or synthetic rock-like samples,the samples made by 3D printing technology have unique advantages,such as higher test repeatability,visualization of rock internal structure and stress distribution.There is thus great potential for the use of 3D printing in the feld of rock mass mechanics.However,3D printing materials also have shortcomings,such as insufcient material strength and accuracy at this stage.Finally,the application prospect of 3D printing technology in rock mass mechanics research is proposed. 展开更多
关键词 3D printing Rock mass mechanics Prefabricated cracks Rock-like material Fractured rock mass
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Quantitative characterization of cell physiological state based on dynamical cell mechanics for drug efficacy indication 被引量:1
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作者 Shuang Ma Junfeng Wu +5 位作者 Zhihua Liu Rong He Yuechao Wang Lianqing Liu Tianlu Wang Wenxue Wang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第4期388-402,共15页
Cell mechanics is essential to cell development and function,and its dynamics evolution reflects the physiological state of cells.Here,we investigate the dynamical mechanical properties of single cells under various d... Cell mechanics is essential to cell development and function,and its dynamics evolution reflects the physiological state of cells.Here,we investigate the dynamical mechanical properties of single cells under various drug conditions,and present two mathematical approaches to quantitatively characterizing the cell physiological state.It is demonstrated that the cellular mechanical properties upon the drug action increase over time and tend to saturate,and can be mathematically characterized by a linear timeinvariant dynamical model.It is shown that the transition matrices of dynamical cell systems significantly improve the classification accuracies of the cells under different drug actions.Furthermore,it is revealed that there exists a positive linear correlation between the cytoskeleton density and the cellular mechanical properties,and the physiological state of a cell in terms of its cytoskeleton density can be predicted from its mechanical properties by a linear regression model.This study builds a relationship between the cellular mechanical properties and the cellular physiological state,adding information for evaluating drug efficacy. 展开更多
关键词 Cellular mechanical properties CYTOSKELETON Drug efficacy evaluation Cell system modelling Linear regression
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Porosity, permeability and rock mechanics of Lower Silurian Longmaxi Formation deep shale under temperature-pressure coupling in the Sichuan Basin, SW China 被引量:3
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作者 SUN Chuanxiang NIE Haikuan +5 位作者 SU Haikun DU Wei LU Ting CHEN Yalin LIU Mi LI Jingchang 《Petroleum Exploration and Development》 2023年第1期85-98,共14页
To investigate the porosity, permeability and rock mechanics of deep shale under temperature-pressure coupling, we selected the core samples of deep shale from the Lower Silurian Longmaxi Formation in the Weirong and ... To investigate the porosity, permeability and rock mechanics of deep shale under temperature-pressure coupling, we selected the core samples of deep shale from the Lower Silurian Longmaxi Formation in the Weirong and Yongchuan areas of the Sichuan Basin for porosity and permeability experiments and a triaxial compression and sound wave integration experiment at the maximum temperature and pressure of 120 ℃ and 70 MPa. The results show that the microscopic porosity and permeability change and the macroscopic rock deformation are mutually constrained, both showing the trend of steep and then gentle variation. At the maximum temperature and pressure, the porosity reduces by 34%–71%, and the permeability decreases by 85%–97%. With the rising temperature and pressure, deep shale undergoes plastic deformation in which organic pores and clay mineral pores are compressed and microfractures are closed, and elastic deformation in which brittle mineral pores and rock skeleton particles are compacted. Compared with previous experiments under high confining pressure and normal temperature,the experiment under high temperature and high pressure coupling reveals the effect of high temperature on stress sensitivity of porosity and permeability. High temperature can increase the plasticity of the rock, intensify the compression of pores due to high confining pressure, and induce thermal stress between the rock skeleton particles, allowing the reopening of shale bedding or the creation of new fractures along weak planes such as bedding, which inhibits the decrease of permeability with the increase of temperature and confining pressure. Compared with the triaxial mechanical experiment at normal temperature, the triaxial compression experiment at high temperature and high pressure demonstrates that the compressive strength and peak strain of deep shale increase significantly due to the coupling of temperature and pressure. The compressive strength is up to 435 MPa and the peak strain exceeds 2%, indicating that high temperature is not conducive to fracture initiation and expansion by increasing rock plasticity. Lithofacies and mineral composition have great impacts on the porosity, permeability and rock mechanics of deep shale. Shales with different lithologies are different in the difficulty and extent of brittle failure. The stress-strain characteristics of rocks under actual geological conditions are key support to the optimization of reservoir stimulation program. 展开更多
关键词 Sichuan Basin Longmaxi Formation deep shale gas POROSITY PERMEABILITY rock mechanics high temperature and high pressure triaxial compression
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