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The Fate of Supersymmetry in Quantum Field Theories
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作者 Risto Raitio 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期609-620,共12页
We analyze the significance of supersymmetry in two topological models and the standard model (SM). We conclude that the two topological field theory models favor hidden supersymmetry. The SM superpartners, instead, h... We analyze the significance of supersymmetry in two topological models and the standard model (SM). We conclude that the two topological field theory models favor hidden supersymmetry. The SM superpartners, instead, have not been found. 展开更多
关键词 Topological Field Theory SUPERSYMMETRY Chern-Simons Model
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Dual Instinct and Structural Theories: DSM-5-TR
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作者 Lawrence Greenman 《Open Journal of Psychiatry》 2024年第4期374-379,共6页
The genetic based Dual Instinct Theory is determined by evolutionary history. Aggression is required for survival and sex for propagation of species. Aggressive and sexual drive derivatives with their corresponding de... The genetic based Dual Instinct Theory is determined by evolutionary history. Aggression is required for survival and sex for propagation of species. Aggressive and sexual drive derivatives with their corresponding defence mechanisms are combined with biologically based stages of infant/child development and the functional entity of Structural Theory. This model of human nature is the applied to the diagnostic categories of DSM-5-TR. Objectives: To follow the innate Dual Instinct Theory from life to death and through Artificial Intelligence;connect it with biological stages of development of the Structural Theory and illustrate its manifestations in DSM-5-TR classifications. Method: Review of selected published literature. Applying the principle of focus and cognition of informed clinical observation of innate drive derivatives in conjunction with The Structural Theory. Both theories are functional entities with no structures involved. Sigmund Freud’s biologically based stages of development;oral, anal, genital pubic, adult, and geriatric along with a variety of unconscious, automatic, and persistent defense mechanisms are selectively folded into diagnosis listed in the manual. 展开更多
关键词 Dual Instincts Structural Theory Stages of Development Drive Derivatives Mechanisms of Defense
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Special Relativity’s “Newtonization” in Complex “Para-Space”: The Two Theories Equivalence Question
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作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第7期2421-2451,共31页
Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The ... Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The actual aim, however, is an additional analysis of the physical and para-physical phenomena’ behavior as we formally transport observable mechanical phenomena [motion] to non-real interior of the complex domain. As it turns out, such procedure, when properly set, corresponds to transition from relativistic to more classic (or, possibly, just classic) kind of the motion. This procedure, we call the “Newtonization of relativistic physical quantities and phenomena”, first of all, includes the mechanical motion’s characteristics in the C3. The algebraic structure of vector spaces was imposed and analyzed on both: the set of all relativistic velocities and on the set of the corresponding to them “Galilean” velocities. The key point of the analysis is realization that, as a matter of fact, the relativistic theory and the classical are equivalent at least as for the kinematics. This conclusion follows the fact that the two defined structures of topological vector spaces i.e., the structure imposed on sets of all relativistic velocities and the structure on set of all “Galilean” velocities, are both diffeomorphic in their topological parts and are isomorphic as the vector spaces. As for the relativistic theory, the two approaches: the hyperbolic (“classical” SR) with its four-vector formalism and Euclidean, where SR is modeled by the complex para-space C3, were analyzed and compared. 展开更多
关键词 Special Relativity’s Hyperbolic Versus Circular Versions Galilean Kinematics Partial Equivalence of SR and Newton’s theories Algebra of Relativistic and the Corresponding Galilean Velocities
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Chinese Education Modernization:A Case Study on Ideological and Political Theories Teaching in All Courses with Organic Integration of Cultural Literacy and Political Education
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作者 Zongyu Gan 《Journal of Contemporary Educational Research》 2024年第5期172-176,共5页
Chinese education modernization is integral to Chinese modernization,and is of leading significance to the further advancement of Chinese modernization and the great rejuvenation of the Chinese nation.In this paper,ta... Chinese education modernization is integral to Chinese modernization,and is of leading significance to the further advancement of Chinese modernization and the great rejuvenation of the Chinese nation.In this paper,taking ideological and political theories teaching in all courses as an example,an attempt is made to organically integrate cultural literacy and political education under the vision of Chinese education modernization,and“gathers knowledge heritage in the dissemination of value and leads the values in the dissemination of knowledge,”thereby training students into highcaliber talents with good and all-round moral,intellectual,physical,aesthetical,and labor grounding. 展开更多
关键词 Chinese education modernization Ideological and political theories teaching in all courses EDUCATION
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A review of rockburst:Experiments,theories,and simulations 被引量:11
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作者 Manchao He Tai Cheng +1 位作者 Yafei Qiao Hongru Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第5期1312-1353,共42页
Rockburst is becoming a huge challenge for the utilization of deep underground space.Extensive efforts have been devoted to investigating the rockburst behavior and mechanism experimentally,theoretically,and numerical... Rockburst is becoming a huge challenge for the utilization of deep underground space.Extensive efforts have been devoted to investigating the rockburst behavior and mechanism experimentally,theoretically,and numerically.The aim of this review is to discuss the novel development and the state-of-the-art in experimental techniques,theories,and numerical approaches proposed for rockburst.The definition and classification of rockburst are first summarized with an in-depth comparison among them.Then,the available laboratory experimental technologies for rockburst are reviewed in terms of indirect and direct approaches,with the highlight of monitoring technologies and data analysis methods.Some key rockburst influencing factors(i.e.size and shape,rock types,stress state,water content,and temperature)are analyzed and discussed based on collected data.After that,rockburst theories and mechanisms are discussed and evaluated,as well as the microscopic observation.The simulation approaches of rockburst are also summarized with the highlight of optional novel numerical methods.The accuracy,stability,and reliability of different experimental,theoretical and numerical approaches are also compared and assessed in each part.Finally,a summary and some aspects of prospective research are presented. 展开更多
关键词 ROCKBURST Experimental techniques Numerical simulation THEORY MECHANISM
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Theories and applications of earthquake-induced gravity variation:Advances and perspectives 被引量:1
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作者 He Tang Wenke Sun 《Earthquake Science》 2023年第5期376-415,共40页
Earthquake-induced gravity variation refers to changes in the earth’s gravity field associated with seismic activities.In recent years,development in the theories has greatly promoted seismic deformation research,lay... Earthquake-induced gravity variation refers to changes in the earth’s gravity field associated with seismic activities.In recent years,development in the theories has greatly promoted seismic deformation research,laying a solid theoretical foundation for the interpretation and application of seismological gravity monitoring.Traditional terrestrial gravity measurements continue to play a significant role in studies of interseismic,co-seismic,and post-seismic gravity field variations.For instance,superconducting gravimeter networks can detect co-seismic gravity change at the sub-micro Gal level.At the same time,the successful launch of satellite gravity missions(e.g.,the Gravity Recovery and Climate Experiment or GRACE)has also facilitated applied studies of the gravity variation associated with large earthquakes,and several remarkable breakthroughs have been achieved.The progress in gravity observation technologies(e.g.,GRACE and superconducting gravimetry)and advances in the theories have jointly promoted seismic deformation studies and raised many new research topics.For example,superconducting gravimetry has played an important role in analyses of episodic tremor,slow-slip events,and interseismic strain patterns;the monitoring of transient gravity signals and related theories have provided a new perspective on earthquake early warning systems;the mass transport detected by the GRACE satellites several months before an earthquake has brought new insights into earthquake prediction methods;the use of artificial intelligence to automatically identify tiny gravity change signals is a new approach to accurate and rapid determination of earthquake magnitude and location.Overall,many significant breakthroughs have been made in recent years,in terms of the theory,application,and observation measures.This article summarizes the progress,with the aim of providing a reference for seismologists and geodetic researchers studying the phenomenon of gravity variation,advances in related theories and applications,and future research directions in this discipline. 展开更多
关键词 earthquake-induced gravity variation seismic dislocation theory time-varying gravity satellite gravity missions pre-P gravity signals superconducting gravimetry
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Multiscale Theories and Applications:From Microstructure Design to Macroscopic Assessment for Carbon Nanotubes Networks
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作者 Jiachao Ji Yulin Jin +2 位作者 Anping Hua Chunhua Zhu Junhua Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期18-35,共18页
Carbon nanotube(CNT)networks enable CNTs to be used as building blocks for synthesizing novel advanced materials,thus taking full advantage of the superior properties of individual CNTs.Multiscale analyses have to be ... Carbon nanotube(CNT)networks enable CNTs to be used as building blocks for synthesizing novel advanced materials,thus taking full advantage of the superior properties of individual CNTs.Multiscale analyses have to be adopted to study the load transfer mechanisms of CNT networks from the atomic scale to the macroscopic scale due to the huge computational cost.Among them,fully resolved structural features include the graphitic honeycomb lattice(atomic),inter-tube stacking(nano)and assembly(meso)of CNTs.On an atomic scale,the elastic properties,ultimate stresses,and failure strains of individual CNTs with distinct chiralities and radii are obtained under various loading conditions by molecular mechanics.The dependence of the cohesive energies on spacing distances,crossing angles,size and edge effects between two CNTs is analyzed through continuum modeling in nanoscale.The mesoscale models,which neglect the atomic structures of individual CNTs but retain geometrical information about the shape of CNTs and their assembly into a network,have been developed to study the multi-level mechanism of material deformation and microstructural evolution in CNT networks under stretching,from elastic elongation,strengthening to damage and failure.This paper summarizes the multiscale theories mentioned above,which should provide insight into the optimal assembling of CNT network materials for elevated mechanical performance. 展开更多
关键词 Carbon nanotube networks Hierarchical structures Multiscale theories Mesoscale model
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Static Analysis of Anisotropic Doubly-Curved Shell Subjected to Concentrated Loads Employing Higher Order Layer-Wise Theories
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作者 Francesco Tornabene Matteo Viscoti Rossana Dimitri 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1393-1468,共76页
In the presentmanuscript,a Layer-Wise(LW)generalizedmodel is proposed for the linear static analysis of doublycurved shells constrained with general boundary conditions under the influence of concentrated and surface ... In the presentmanuscript,a Layer-Wise(LW)generalizedmodel is proposed for the linear static analysis of doublycurved shells constrained with general boundary conditions under the influence of concentrated and surface loads.The unknown field variable is modelled employing polynomials of various orders,each of them defined within each layer of the structure.As a particular case of the LW model,an Equivalent Single Layer(ESL)formulation is derived too.Different approaches are outlined for the assessment of external forces,as well as for non-conventional constraints.The doubly-curved shell is composed by superimposed generally anisotropic laminae,each of them characterized by an arbitrary orientation.The fundamental governing equations are derived starting from an orthogonal set of principal coordinates.Furthermore,generalized blending functions account for the distortion of the physical domain.The implementation of the fundamental governing equations is performed bymeans of the Generalized Differential Quadrature(GDQ)method,whereas the numerical integrations are computed employing theGeneralized IntegralQuadrature(GIQ)method.In the post-processing phase,an effective procedure is adopted for the reconstruction of stress and strain through-the-thickness distributions based on the exact fulfillment of three-dimensional equilibrium equations.A series of systematic investigations are performed in which the static response of structures with various curvatures and lamination schemes,calculated by the present methodology,have been successfully compared to those ones obtained fromrefined finite element three-dimensional simulations.Even though the present LW approach accounts for a two-dimensional assessment of the structural problem,it is capable of well predicting the three-dimensional response of structures with different characteristics,taking into account a reduced computational cost and pretending to be a valid alternative to widespread numerical implementations. 展开更多
关键词 Concentrated load doubly-curved shells generalized differential quadrature laminated anisotropic materials layer-wise theory mapping technique
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Research and Exploration on Ideological and Political Theories Teaching in the Course of Soil Science Experiment:Taking Pingdingshan University as an Example
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作者 Xining GENG Yanjiao LI +3 位作者 Weishuang TONG Shiping CHENG Pengqiang YAO Fengqin HUANG 《Asian Agricultural Research》 2023年第12期61-63,共3页
Experimental course is an important link of ideological and political education in colleges and universities under the new situation,and plays an important role in the construction of ideological and political theorie... Experimental course is an important link of ideological and political education in colleges and universities under the new situation,and plays an important role in the construction of ideological and political theories teaching in the course.Taking Pingdingshan University as an example,by introducing the real soil cases in Pingdingshan area,the ideological and political elements of the course are integrated into the teaching links of laboratory safety training,self-study before class,experimental teaching implementation,evaluation and improvement.By implementing the concept of"All-round Education"in experimental teaching,we are committed to realizing the comprehensive coverage of value shaping,knowledge inheritance and ability training,and explore and practice the reform of ideological and political theories teaching in the course of Soil Science Experiment. 展开更多
关键词 Soil Science EXPERIMENT Ideological and POLITICAL theories TEACHING in the COURSE TEACHING LINK
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On complete and micropolar-based incomplete strain gradient theories for periodic lattice structures
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作者 Zeyang CHI Jinxing LIU A.K.SOH 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第10期1651-1674,共24页
The micropolar(MP) and strain gradient(SG) continua have been generally adopted to investigate the relations between the macroscopic elastic constants and the microstructural geometric parameters. Owing to the fact th... The micropolar(MP) and strain gradient(SG) continua have been generally adopted to investigate the relations between the macroscopic elastic constants and the microstructural geometric parameters. Owing to the fact that the microrotation in the MP theory can be expressed in terms of the displacement gradient components, we may regard the MP theory as a particular incomplete SG theory called the MPSG theory,compared with the existing SG theories which are deemed complete since all the SGs are included. Taking the triangular lattice comprising zigzag beams as an example, it is found that as the angle of the zigzag beams increases, the bending of the beams plays a more important role in the total strain energy, and the difference between the results by the two theories gradually decreases. Finally, the models are verified with the pure bending and simple shear of lattices by comparing with the results obtained by the finite element method(FEM)-based structure analyses. 展开更多
关键词 periodic lattice metamaterial energy principle HOMOGENIZATION micropolar(MP) strain gradient(SG)theory
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Creating the Role of Rural Teachers as New Rural Sages under the Background of Rural Revitalization Based on Organizational Change and Planned Happenstance Theories
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作者 LIN Jiangfeng YANG Shuai SHAN Yingyu 《Journal of Landscape Research》 2023年第6期65-68,72,共5页
In the context of rural revitalization,people are re-examining the issue of creating the role of teachers as“new rural sages”.However,most of previous studies ignored the school organizational change in the process ... In the context of rural revitalization,people are re-examining the issue of creating the role of teachers as“new rural sages”.However,most of previous studies ignored the school organizational change in the process of reform.The planned happenstance suggests that teachers should maintain a positive mindset about the eventualities in their careers.Based on the organizational change theory,this paper gave some advice to help teachers in playing a role of new rural sages:①rooting in local culture and enhancing teachers’sense of belonging,②providing compensation for teachers in a targeted way,and③providing a comprehensive and objective evaluation mechanism for ensuring teachers’participation in social governance. 展开更多
关键词 Rural teacher School organizational reform Planned happenstance theory New rural sage
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Reflections on Cultivating Critical Thinking in Foreign Language Courses in the Context of Integrating Ideological and Political Theories in All Courses
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作者 Xu Haiyan Wang Yaguang 《Contemporary Social Sciences》 2023年第5期129-140,共12页
The education reform of integrating ideological and political theories in all courses is crucial in fostering virtue through education.In the new era,foreign language courses are increasingly prominent in moral educat... The education reform of integrating ideological and political theories in all courses is crucial in fostering virtue through education.In the new era,foreign language courses are increasingly prominent in moral education.Learning a language is not just about mastering its language form but also about critically examining the cultural connotations and thinking patterns embedded within it.Therefore,cultivating students’critical thinking skills should be a key focus in foreign language education.First,this paper examines the importance of fostering students’critical thinking in foreign language courses.Second,considering the characteristics of Chinese college foreign language courses,we propose that if we want to cultivate critical thinking among students through foreign language courses,we need to effect pattern transformations across four aspects:teaching philosophy,teaching content,teaching methodology,and teaching evaluation.These transformations also present requirements for foreign language teachers.They should focus on enhancing their comprehensive literacy,including ideological and political literacy,teaching design skills,and the ability to integrate teaching materials with logical thinking.And China’s Standards of English Language Ability(the CSE)serves as an important reference indicator for implementing these transformations. 展开更多
关键词 ideological and political theories teaching in foreign language courses critical thinking the CSE
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The Principle of Differentiation into Physical and Mathematical Theories
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作者 Anatoly Parfyonov 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1208-1216,共9页
The article formulates the main principle of physics, which underlies this science. This principle has been called by the author of this article the Principle of differentiation into physical and mathematical theories... The article formulates the main principle of physics, which underlies this science. This principle has been called by the author of this article the Principle of differentiation into physical and mathematical theories. The article gives examples of the application of this principle in quantum mechanics and cosmology. A more detailed proof of the principle of equivalence of the electromagnetic field and the field of strong interaction to a free material particle is given. This principle, formulated in the article “Electrodynamics in Curvilinear Coordinates and the Equation of a Geodesic Line”, revealed the nature of the mass of elementary particles and became the basis for the formulation of the Principle of differentiation into physical and mathematical theories. 展开更多
关键词 Origin of the Universe Expansion of the Universe Corpuscular-Wave Dualism The Principle of Differentiation into Physical and Mathematical theories
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元宇宙视域下数字文旅用户参与行为的影响因素 被引量:4
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作者 张宁 常帅峰 袁勤俭 《图书馆论坛》 北大核心 2024年第1期94-104,共11页
元宇宙为数字文旅提供了全新的表现形式,探究元宇宙视域下数字文旅用户的参与行为有助于元宇宙技术方和数字文旅内容生产方明确如何激励用户参与,改善交互方式使用户获得更好的互动体验。文章选取相关研究对象进行访谈,应用扎根理论,结... 元宇宙为数字文旅提供了全新的表现形式,探究元宇宙视域下数字文旅用户的参与行为有助于元宇宙技术方和数字文旅内容生产方明确如何激励用户参与,改善交互方式使用户获得更好的互动体验。文章选取相关研究对象进行访谈,应用扎根理论,结合SOR理论和MOA框架构建元宇宙视域下数字文旅用户参与行为的影响因素模型。研究发现:感知因素直接影响元宇宙视域下数字文旅用户的参与行为,内部动机和外部反馈两个维度通过感知因素的中介作用间接影响元宇宙视域下数字文旅用户的参与行为,机会条件和能力限制会调节感知因素对参与行为的影响。 展开更多
关键词 元宇宙 数字文旅 SOR理论 MOA框架 扎根理论 参与行为
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“数据”可否纳入知识产权客体范畴? 被引量:5
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作者 肖冬梅 《政法论丛》 北大核心 2024年第1期137-148,共12页
《民法总则》(草案)第108条将“数据信息”纳入知识产权客体范畴,虽然该规定最终未获通过,但却引发了学界和业界的热议,数据可否纳入知识产权客体范畴的讨论方兴未艾。根据“信息链”理论,事实、数据、信息、知识和情报之间是呈现一种... 《民法总则》(草案)第108条将“数据信息”纳入知识产权客体范畴,虽然该规定最终未获通过,但却引发了学界和业界的热议,数据可否纳入知识产权客体范畴的讨论方兴未艾。根据“信息链”理论,事实、数据、信息、知识和情报之间是呈现一种由下至上逐步提炼加工的链式关系,数据与信息、知识、情报之间依次包含。但数据并不符合知识产权客体的一般特征,若将“数据”整体直接纳入知识产权客体的范畴,会冲击已有的权能和体系,影响知识产权客体家族的统一性和协调性。应对数据进行分类保护,在现有知识产权保护基础之上,增设数据产权保护模式,数据主体就个人原始数据享有数据人格权和数据财产权;企业就其加工处理取得的衍生数据享有数据财产权,企业这种财产权利取得的门槛低于知识产权取得,不必要求独创性、创造性或显著性等知识产权客体的一般特征,宜采取弱保护模式。 展开更多
关键词 数据 知识产权客体 原型范畴理论 家族相似性理论
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中国情境下的乡村创业:一个研究框架的构建 被引量:1
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作者 刘海建 李海燕 《河海大学学报(哲学社会科学版)》 北大核心 2024年第2期12-24,共13页
乡村创业是推进乡村产业振兴的关键抓手和实际切入点。“千村示范、万村整治”工程创造的成功经验和实践范例,不仅成为一份中国式现代化的乡村样本,还为我国乡村创业研究提供了丰富的素材,其中乡村情境是与创业活动紧密交互且不可剥离... 乡村创业是推进乡村产业振兴的关键抓手和实际切入点。“千村示范、万村整治”工程创造的成功经验和实践范例,不仅成为一份中国式现代化的乡村样本,还为我国乡村创业研究提供了丰富的素材,其中乡村情境是与创业活动紧密交互且不可剥离的要素,是实践和理论的研究焦点。通过梳理全球乡村创业研究脉络发现,异质性情境决定了乡村创业研究的侧重点,使不同区域开展的研究呈现发展不平衡且碎片化的特征。为推进我国乡村创业研究的内生理论发展,通过紧扣乡村创业活动与情境的互动这一核心特征,在梳理多维情境中乡村创业研究的基础上,构建中国情境下开展乡村创业研究的综合框架。该框架遵循资源依赖理论的逻辑,通过审视乡村情境各维度蕴含的资源,分析乡村创业同情境之间的资源依赖程度,强调最契合动态嵌入模式的选择。在时间、空间双重维度中,该嵌入模式的动态特征决定了乡村创业实现路径会不断演化甚至有双元嵌入融合的可能。结论进一步厘清了乡村创业的理论边界,有助于我国乡村创业研究的理论化和系统化发展,表明在学习“千村示范、万村整治”工程所蕴含的发展理念、工作方法和推进机制时需要因地制宜,分类施策,以当地乡村情境为核心,合理编排相适配的资源,选择恰当的嵌入模式以促进当地产业有序、良性发展。 展开更多
关键词 乡村振兴 乡村创业 乡村情境 资源依赖理论 内生理论 深度嵌入 广度嵌入
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砂土中能量桩单桩水平承载特性模型试验研究 被引量:2
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作者 陈志雄 赵华 +3 位作者 王成龙 丁选明 孔纲强 高学成 《工程力学》 EI CSCD 北大核心 2024年第3期114-123,共10页
为探究能量桩单桩水平承载特性,针对砂土中能量桩在水平荷载下的承载特性进行研究,基于模型试验,分析了水平荷载作用下能量桩在制冷和加热过程中的桩顶位移、桩前土压力以及桩身弯矩等的变化规律。研究结果表明:制冷会引起能量桩桩顶水... 为探究能量桩单桩水平承载特性,针对砂土中能量桩在水平荷载下的承载特性进行研究,基于模型试验,分析了水平荷载作用下能量桩在制冷和加热过程中的桩顶位移、桩前土压力以及桩身弯矩等的变化规律。研究结果表明:制冷会引起能量桩桩顶水平位移略微增大,增量为0.48%D(D为桩体直径),而加热会引起较大的桩顶水平位移,达到了2.38%D;制冷和加热在初始阶段会引起桩前土压力增大,初始增长阶段结束后,土压力变化较小,多为缓慢增长或基本不变。相较于初始土压力,制冷和加热结束时的土压力基本呈增长趋势,仅个别埋深处土压力减小。制冷过程中,埋深0%L~40%L(L为有效桩长)范围内的弯矩增大,埋深40%L~100%L位置处的弯矩变化较小;加热过程中,埋深0%L~60%L范围内的弯矩均有所增大,0%L~40%L位置处的弯矩增大最为明显。制冷和加热过程中均在20%L处产生了最大弯矩,最大弯矩的增加量分别为9.93%和10.32%。进一步基于圆孔扩张理论提出了弯矩计算的理论解,并与试验结果进行对比分析,理论计算值与实测值较为吻合。 展开更多
关键词 能量桩 水平承载特性 模型试验 砂土 圆孔扩张理论
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干旱形成机制与预测理论方法及其灾害风险特征研究进展与展望 被引量:1
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作者 张强 李栋梁 +12 位作者 姚玉璧 王芝兰 王莺 王静 王劲松 王素萍 岳平 王慧 韩兰英 司东 李清泉 曾刚 王欢 《气象学报》 CAS CSCD 北大核心 2024年第1期1-21,共21页
在全球变暖背景下,干旱事件发生的频率和强度不断增大、影响不断加重,干旱发生规律的异常性和机制的复杂性也更为突出,对干旱形成机制、预测理论方法及灾害风险变化规律等方面都提出了新的挑战,也制约了当前干旱预测、预警及其灾害防控... 在全球变暖背景下,干旱事件发生的频率和强度不断增大、影响不断加重,干旱发生规律的异常性和机制的复杂性也更为突出,对干旱形成机制、预测理论方法及灾害风险变化规律等方面都提出了新的挑战,也制约了当前干旱预测、预警及其灾害防控能力的提高。近年来,在国家重点基础研究发展计划(973计划)课题等多个国家级项目支持下,已在干旱灾害形成机制与预测理论方法及其风险特征方面取得了一系列新成果。通过动力诊断、数值模拟和田间试验等方法,开展了干旱形成的多因子协同作用和多尺度叠加机制、干旱致灾过程的逐阶递进特征,以及干旱灾害风险分布演化的主控因素等方面的研究。对如下几方面的新进展进行了系统总结归纳:(1)厘清了全球变暖背景下青藏高原热力、海温、夏季风、遥相关等多因子对干旱形成的作用机制。(2)发现了降水亏缺时间尺度和农作物不同生长阶段的干旱敏感性规律。(3)揭示了变暖背景下典型区域干旱灾害风险分布及其变异的新特征;构建了干旱灾害风险新概念模型。(4)研发了东亚季风区的季节和次季节干旱集成预测系统。在总结归纳已取得研究成果的基础上,对未来干旱形成机制及其灾害风险科学研究进行了展望,提出了5个重点研究方向:(1)多因子联动及其多尺度叠加效应对干旱形成的影响;(2)系统整合人类活动和决策以及相关反馈的气候模式研究;(3)揭示陆-气耦合和大气环流协同作用对干旱的影响;(4)认识干旱灾害对粮食安全和生态安全影响的关键过程;(5)提高不同气候情景下干旱预估的准确度。 展开更多
关键词 干旱灾害 形成机制 预测理论 风险特征 协同作用
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护理研究中理论的构建及验证
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作者 王青 朱明月 +1 位作者 丁晓彤 李峥 《护理研究》 北大核心 2024年第12期2083-2087,共5页
护理理论构建和发展是拓展护理学科知识范畴、提升护理学科科学性的关键。以Walker和Avant的理论构建策略为切入点,围绕理论构建的全过程,对护理理论的相关概念、理论构建及理论验证的基本方法进行阐述,旨在为护理研究者构建并应用具有... 护理理论构建和发展是拓展护理学科知识范畴、提升护理学科科学性的关键。以Walker和Avant的理论构建策略为切入点,围绕理论构建的全过程,对护理理论的相关概念、理论构建及理论验证的基本方法进行阐述,旨在为护理研究者构建并应用具有中国特色的护理理论提供参考,并促进护理知识体系的发展。 展开更多
关键词 护理理论 护理研究 理论构建 理论验证 概念
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基于供需理论的生成式人工智能赋能情报工作范式模型构建与应用研究 被引量:2
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作者 白如江 陈鑫 任前前 《情报理论与实践》 北大核心 2024年第1期75-83,共9页
[目的/意义]当前生成式人工智能的发展对社会产生了强烈冲击。为响应国家创新发展的迫切需求,如何利用生成式人工智能更好地完成情报工作,以满足用户的情报需求,已成为当前情报学领域关注的热点问题。[方法/过程]基于供需理论提出从数... [目的/意义]当前生成式人工智能的发展对社会产生了强烈冲击。为响应国家创新发展的迫切需求,如何利用生成式人工智能更好地完成情报工作,以满足用户的情报需求,已成为当前情报学领域关注的热点问题。[方法/过程]基于供需理论提出从数据供给侧(Supply)、智慧情报分析中台(Analysis)、情报需求侧(Demand)三方构建生成式人工智能赋能情报工作范式模型——SAD范式模型,深入分析生成式人工智能赋能情报工作机理,并结合国际前沿项目案例探讨生成式人工智能与情报工作的前瞻性融合发展。[结果/结论]生成式人工智能赋能情报工作范式模型SAD,可以更好地促进生成式人工智能赋能情报工作的各个环节,提高情报工作效率,为情报工作范式研究提供了新思路。 展开更多
关键词 供需理论 生成式人工智能 情报工作 范式模型
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