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On the Lebesgue Integral and the Lebesgue Measure: Mathematical Applications in Some Sectors of Chern-Simons Theory and Yang-Mills Gauge Theory and Mathematical Connections with Some Sectors of String Theory and Number Theory
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作者 Michele Nardelli 《Journal of Modern Physics》 2025年第1期93-132,共40页
In this paper, in Section 1, we have described some equations and theorems concerning the Lebesgue integral and the Lebesgue measure. In Section 2, we have described the possible mathematical applications, of Lebesgue... In this paper, in Section 1, we have described some equations and theorems concerning the Lebesgue integral and the Lebesgue measure. In Section 2, we have described the possible mathematical applications, of Lebesgue integration, in some equations concerning various sectors of Chern-Simons theory and Yang-Mills gauge theory, precisely the two dimensional quantum Yang-Mills theory. In conclusion, in Section 3, we have described also the possible mathematical connections with some sectors of String Theory and Number Theory, principally with some equations concerning the Ramanujan’s modular equations that are related to the physical vibrations of the bosonic strings and of the superstrings, some Ramanujan’s identities concerning π and the zeta strings. 展开更多
关键词 Lebesgue Integral Chern-Simons theory Yang-Mills Gauge theory String theory Number theory
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First-principles prediction of shock Hugoniot curves of boron,aluminum,and silicon from stochastic density functional theory
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作者 Tao Chen Qianrui Liu +1 位作者 Chang Gao Mohan Chen 《Matter and Radiation at Extremes》 2025年第5期73-83,共11页
By adopting stochastic density functional theory(SDFT)and mixed stochastic-deterministic density functional theory(MDFT)methods,we perform first-principles calculations to predict the shock Hugoniot curves of boron(pr... By adopting stochastic density functional theory(SDFT)and mixed stochastic-deterministic density functional theory(MDFT)methods,we perform first-principles calculations to predict the shock Hugoniot curves of boron(pressure P=7.9×10^(3)-1.6×10^(6) GPa and temperature T=25-2800 eV),silicon(P=2.6×10^(3)-7.9×10^(5) GPa and T=21.5-1393 eV),and aluminum(P=5.2×10^(3)-9.0×10^(5) GPa and T=25-1393 eV)over wide ranges of pressure and temperature.In particular,we systematically investigate the impact of different cutoff radii in norm-conserving pseudopotentials on the calculated properties at elevated temperatures,such as pressure,ionization energy,and equation of state.By comparing the SDFT and MDFT results with those of other first-principles methods,such as extended first-principles molecular dynamics and path integral Monte Carlo methods,we find that the SDFT and MDFT methods show satisfactory precision,which advances our understanding of first-principles methods when applied to studies of matter at extremely high pressures and temperatures. 展开更多
关键词 mixed stochastic deterministic density functional theory BORON shock hugoniot curves stochastic density functional theory stochastic density functional theory sdft ALUMINUM SILICON first principles calculations
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Comparing Three of the Leadership Theories: Leader-Member Exchange Theory,transformational Leadership and Team Leadership
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作者 王子涵 《中国校外教育(上旬)》 2013年第S2期122-124,共3页
Leadership is a complex process.It is one of the most researched areas around the world.It has gained importance in every walk of life from politics to business and from education to social organizations.According to ... Leadership is a complex process.It is one of the most researched areas around the world.It has gained importance in every walk of life from politics to business and from education to social organizations.According to the study of"Leadership in Adult Education Venues",here has a much more clear recognition of leadership:leadership is a process whereby an individual influences a group of individuals to achieve a common goal.There are many approaches of leadership throughout the study of this class,the three theories of leadership I choose to describe in this paper are:Leader-Member Exchange(LMX)Theory,Transformational Leadership,and Team Leadership. 展开更多
关键词 Leader-Member EXCHANGE theory Transformational LEA
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RENEWAL OF BASIC LAWS AND PRINCIPLES FOR POLAR CON-TINUUM THEORIES (Ⅱ)—MICROMORPHIC CONTINUUM THEORY AND COUPLE STRESS THEORY 被引量:2
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作者 戴天民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第10期1126-1133,共8页
The purpose is to reestablish the balance laws of momentum, angular momentum and energy and to derive the corresponding local and nonlocal balance equations for micromorphic continuum mechanics and couple stress theor... The purpose is to reestablish the balance laws of momentum, angular momentum and energy and to derive the corresponding local and nonlocal balance equations for micromorphic continuum mechanics and couple stress theory. The desired results for micromorphic continuum mechanics and couple stress theory are naturally obtained via direct transitions and reductions from the coupled conservation law of energy for micropolar continuum theory, respectively. The basic balance laws and equations for micromorphic continuum mechanics and couple stress theory are constituted by combining these results derived here and the traditional conservation laws and equations of mass and microinertia and the entropy inequality. The incomplete degrees of the former related continuum theories are clarified. Finally, some special cases are conveniently derived. 展开更多
关键词 micromorphic continuum couple stress theory COUPLED basic balance law balance equation
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Shandong Provincial Vocational Education Teaching Reform Research Project“Research and Practice on the Digital Upgrade of Business and Trade Professional Groups in Vocational Colleges from the Perspective of System Theory”(2023075)
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作者 Linkai Han Xin Wan 《Journal of Contemporary Educational Research》 2025年第4期23-28,共6页
This paper focuses on English homework design in compulsory education under the“Double Reduction”policy.It first analyzes the research background and significance,reviews relevant literature at home and abroad,and p... This paper focuses on English homework design in compulsory education under the“Double Reduction”policy.It first analyzes the research background and significance,reviews relevant literature at home and abroad,and points out existing problems.Then,based on constructivist learning theory,multiple intelligences theory,and formative assessment theory,it proposes design principles like reducing burden and increasing efficiency,and design strategies such as layered design.Although the research has limitations,it provides theoretical and practical references for English education reform. 展开更多
关键词 Double Reduction policy English homework design Constructivist learning theory Multiple intelligences theory
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Atif-V2.0:Extending Classical Density Functional Theory with Interfacial Statistical Associating Fluid Theory for Inhomogeneous Associating Fluids
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作者 Xiu-Jun Wang Shi-Chao Li +2 位作者 Jian Zhang Qiu-Hui Chang Jian Jiang 《Chinese Journal of Polymer Science》 2025年第11期2128-2137,I0014,共11页
Understanding the thermodynamic behavior of complex fluids in confined environments is critical for various industrial and natural processes including but not limited to polymer flooding enhanced oil recovery(EOR).In ... Understanding the thermodynamic behavior of complex fluids in confined environments is critical for various industrial and natural processes including but not limited to polymer flooding enhanced oil recovery(EOR).In this work,we develop Atif-V2.0,an extended classical density functional theory(cDFT)framework that integrates the interfacial statistical associating fluid theory(iSAFT)to model multicomponent associating fluids composed of water-soluble polymers,alkanes,and water.Building on the original theoretical framework of Atif for modeling nanoconfined inhomogeneous fluids,Atif-V2.0 embeds explicit solvent and captures additional physical interactions-hydrogen bonding,which are critical in associating fluid systems.The other key feature of Atif-V2.0 is its ability to account for polymer topology.We demonstrate its capability by predicting the equilibrium structure and thermodynamic behavior of branched hydrolyzed polyacrylamide solutions near hard walls with various branching topologies,which provides a robust theoretical tool for the rational design of EOR polymers. 展开更多
关键词 Classical density functional theory Interfacial statistical associating fluid theory Hydrogen bonding Associating fluid
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Discrete and Topological Correspondence Theory for Modal MeetImplication Logic and Modal MeetSemilattice Logic in Filter Semantics
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作者 Fei Liang Zhiguang Zhao 《逻辑学研究》 2025年第3期25-66,共42页
In the present paper,we give a systematic study of the discrete correspondence the-ory and topological correspondence theory of modal meet-implication logic and moda1 meet-semilattice logic,in the semantics provided i... In the present paper,we give a systematic study of the discrete correspondence the-ory and topological correspondence theory of modal meet-implication logic and moda1 meet-semilattice logic,in the semantics provided in[21].The special features of the present paper include the following three points:the first one is that the semantic structure used is based on a semilattice rather than an ordinary partial order,the second one is that the propositional vari-ables are interpreted as filters rather than upsets,and the nominals,which are the“first-order counterparts of propositional variables,are interpreted as principal filters rather than principal upsets;the third one is that in topological correspondence theory,the collection of admissi-ble valuations is not closed under taking disjunction,which makes the proof of the topological Ackermann 1emma different from existing settings. 展开更多
关键词 topological correspondence theory SEMILATTICE modal meet implication logic modal meet semilattice logic discrete correspondence theory semantic structure propositional variables filter semantics
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BASIC EQUATIONS, THEORY AND PRINCIPLE OF COMPUTATIONAL STOCK MARKET (Ⅲ)—BASIC THEORIES
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作者 云天铨 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第8期861-868,共8页
By basic equations, two basic theories are presented: 1.Theory of stock's value v *(t)=v *(0) exp (ar * 2t); 2. Theory of conservation of stock's energy. Let stock's energy be defined as a q... By basic equations, two basic theories are presented: 1.Theory of stock's value v *(t)=v *(0) exp (ar * 2t); 2. Theory of conservation of stock's energy. Let stock's energy be defined as a quadratic function of stock's price v and its derivative , =Av 2+ Bv+C 2+Dv, under the constraint of basic equation, the problem was reduced to a problem of constrained optimization along optimal path. Using Lagrange multiplier and Euler equation of variation method, it can be proved that keeps conservation for any v,. The application of these equations and theories on judgement and analysis of tendency of stock market are given, and the judgement is checked to be correct by the recorded tendency of Shenzhen and Shanghai stock markets. 展开更多
关键词 political economics theory of value of goods variational method Euler equation conservation law
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The Theory of Field-Effect Transistors:XI. The Bipolar Electrochemical Currents(1-2-MOS-Gates on Thin-Thick Pure-Impure Base)
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作者 薩支唐 揭斌斌 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第3期397-409,共13页
The field-effect transistor is inherently bipolar, having simultaneously electron and hole surface and volume channels and currents. The channels and currents are controlled by one or more externally applied transvers... The field-effect transistor is inherently bipolar, having simultaneously electron and hole surface and volume channels and currents. The channels and currents are controlled by one or more externally applied transverse electric fields. It has been known as the unipolar field-effect transistor for 55-years since Shockley's 1952 invention,because the electron-current theory inevitably neglected the hole current from over-specified internal and boundary conditions, such as the electrical neutrality and the constant hole-electrochemical-potential, resulting in erroneous solutions of the internal and terminal electrical characteristics from the electron channel current alone, which are in gross error when the neglected hole current becomes comparable to the electron current, both in subthreshold and strong inversion. This report presents the general theory, that includes both electron and hole channels and currents. The rectangular ( x, y, z) parallelepiped transistors,uniform in the width direction (z-axis),with one or two MOS gates on thin and thick,and pure and impure base, are used to illustrate the two-dimensional effects and the correct internal and boundary conditions for the electric and the electron and hole electrochemical potentials. Complete analytical equations of the DC current-voltage characteristics of four common MOS transistor structures are derived without over-specification: the 1-gate on semi-infinite-thick impure-base (the traditional bulk transistor), the 1-gate on thin impure-silicon layer over oxide-insulated silicon bulk (SOI) ,the 1-gate on thin impure-silicon layer deposited on insulating glass (SOI TFT), and the 2-gates on thin pure-base (FinFETs). 展开更多
关键词 bipolar field-effect transistor theory MOS field-effect transistor simultaneous electron and hole surface and volume channels and currents surface potential two-section short-channel theory double-gate impure-base theory
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About the Conflicts between the Unitary Quantum Theory and the Special and General Relativity Theories
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作者 Leo G. Sapogin V. A. Dzhanibekov +3 位作者 M. A. Moкulsky Yu. A. Ryabov Yu. P. Savin V. I. Utchastkin 《Journal of Modern Physics》 2015年第6期780-785,共6页
The authors discuss contradictions between the principal branches of the modern physical picture of the universe. Space and time have been shown in the Unitary Quantum Theory (UQT) not to be connected one with the oth... The authors discuss contradictions between the principal branches of the modern physical picture of the universe. Space and time have been shown in the Unitary Quantum Theory (UQT) not to be connected one with the other, unlike in the Special Theory of Relativity. In UQT, time becomes Newtonian again, and the growth of the particle’s mass with growing speed proceeds from other considerations of physics. Unlike the quantum theory, the modern gravitation theory (the general theory of relativity) is not confirmed by experiments and needs to be considerably revised. 展开更多
关键词 UNITARY Quantum theory General RELATIVITY SPECIAL RELATIVITY Maxwell Equations LORENTZ TRANSFORMATIONS
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On a Fractal Version of Witten’s M-Theory 被引量:12
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作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2016年第2期135-144,共10页
Starting from Witten’s eleven dimensional M-theory, the present work develops in an analogous way a corresponding dimensional fractal version where . Subsequently, the new fractal formalism is utilized to determine t... Starting from Witten’s eleven dimensional M-theory, the present work develops in an analogous way a corresponding dimensional fractal version where . Subsequently, the new fractal formalism is utilized to determine the measured ordinary energy density of the cosmos which turns out to be intimately linked to the new theory’s fractal dimension via non-integer irrational Lorentzian-like factor: where is Hardy’s probability of quantum entanglement. Consequently, the energy density is found from a limiting classical kinetic energy to be Here, is ‘tHooft’s renormalon of dimensional regularization. The immediate logical, mathematical and physical implication of this result is that the dark energy density of the cosmos must be in astounding agreement with cosmic measurements and observations. 展开更多
关键词 M-theory E-Infinity theory Hardy’s Quantum Entanglement Transfinite Turing Computer Dark Energy Accelerated Cosmic Expansion Noncommutative Geometry Superstring theory Scale Relativity Cantorian-Fractal Spacetime Witten’s theory ‘tHooft Renormalon Pure Gravity Penrose Tiling
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Nursing interventions based on Snyder’s hope theory for depression following percutaneous coronary interventions:A clinical study 被引量:3
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作者 Xiao Wang Hai-Feng Song Si-Min Zhang 《World Journal of Psychiatry》 2025年第2期33-40,共8页
BACKGROUND Patients with depression following coronary heart disease often exhibit insufficient psychological resilience and self-care abilities;therefore,emphasis must be placed on nursing interventions.AIM To analyz... BACKGROUND Patients with depression following coronary heart disease often exhibit insufficient psychological resilience and self-care abilities;therefore,emphasis must be placed on nursing interventions.AIM To analyze the application value of problem-oriented education combined with nursing interventions based on the Snyder hope theory model in depressed patients after percutaneous coronary intervention(PCI).METHODS This study included 150 patients diagnosed with PCI postoperative depression because of coronary heart disease between February 2022 and February 2024.Participants were divided into two groups:A control group(n=75)receiving problem-oriented education and an observation group(n=75)receiving combined nursing interventions based on the Snyder hope theory model.Depression status,psychological resilience,self-care ability,and quality of life were compared between the two groups.RESULTS Before nursing interventions,there were no significant differences between the two groups(P>0.05).After the interventions,depression scores decreased while psychological resilience,self-care ability,and quality of life scores increased significantly in the observation group compared to that in the control group,with statistically significant differences noted(P<0.05).This combined approach can enhance psychological resilience,improve self-care abilities,and elevate the overall quality of life,warranting further promotion in clinical practice.CONCLUSION Combination of problem-oriented education and nursing interventions based on the Snyder hope theory model effectively alleviates depression in patients following PCI for coronary heart disease. 展开更多
关键词 Problem-oriented education Snyder hope theory model Coronary heart disease DEPRESSION Psychological resilience Self-care ability
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Bubble Theory and its Applications in Underwater Explosion, Marine Cavitation, and Seismic Exploration 被引量:1
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作者 Runze Xu Shiping Wang +1 位作者 Hemant J.Sagar Haikun Wang 《哈尔滨工程大学学报(英文版)》 2025年第2期255-284,共30页
Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have bee... Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have been conducted to reveal the mysteries of bubble motion and its mechanisms.These efforts have significantly advanced research in bubble dynamics,where theoretical study is an efficient method for bubble motion prediction.Since Lord Rayleigh introduced the theoretical model of single-bubble motion in incompressible fluid in 1917,theoretical studies have been pivotal in understanding bubble dynamics.This study provides a comprehensive review of the development and applicability of theoretical studies in bubble dynamics using typical theoretical bubble models across different periods as a focal point and an overview of bubble theory applications in underwater explosion,marine cavitation,and seismic exploration.This study aims to serve as a reference and catalyst for further advancements in theoretical analysis and practical applications of bubble theory across marine fields. 展开更多
关键词 Bubble theory Underwater explosion Marine cavitation Seismic exploration
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Mole-inspired Forepaw Design and Optimization Based on Resistive Force Theory 被引量:1
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作者 Tao Zhang Zhaofeng Liang +8 位作者 Hongmin Zheng Zibiao Chen Kunquan Zheng Ran Xu Jiabin Liu Haifei Zhu Yisheng Guan Kun Xu Xilun Ding 《Journal of Bionic Engineering》 2025年第1期171-180,共10页
Moles exhibit highly effective capabilities due to their unique body structures and digging techniques,making them ideal models for biomimetic research.However,a major challenge for mole-inspired robots lies in overco... Moles exhibit highly effective capabilities due to their unique body structures and digging techniques,making them ideal models for biomimetic research.However,a major challenge for mole-inspired robots lies in overcoming resistance in granular media when burrowing with forelimbs.In the absence of effective forepaw design strategies,most robotic designs rely on increased power to enhance performance.To address this issue,this paper employs Resistive Force Theory to optimize mole-inspired forepaws,aiming to enhance burrowing efficiency.By analyzing the relationship between geometric parameters and burrowing forces,we propose several forepaw design variations.Through granular resistance assessments,an effective forepaw configuration is identified and further refined using parameters such as longitudinal and transverse curvature.Subsequently,the Particle Swarm Optimization algorithm is applied to determine the optimal forepaw design.In force-loading tests,the optimized forepaw demonstrated a 79.44%reduction in granular lift force and a 22.55%increase in propulsive force compared with the control group.In robotic burrowing experiments,the optimized forepaw achieved the longest burrow displacement(179.528 mm)and the lowest burrowing lift force(0.9355 mm/s),verifying its effectiveness in reducing the lift force and enhancing the propulsive force. 展开更多
关键词 Resistive force theory Mole-inspired forepaw design Structural optimization Bioinspired robot
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Element Transfer Reaction theory:Scientific connotation and its applications in chemical industry 被引量:1
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作者 Hongen Cao Xinrui Xiao +2 位作者 Xu Zhang Yiyang Zhang Lei Yu 《Chinese Chemical Letters》 2025年第9期4-7,共4页
Element Transfer Reaction(ETR)theory is a new fundamental theory guiding the design of synthetic routes.It analyses problems from a brand-new perspective of element circulation,decomposing the factors affecting synthe... Element Transfer Reaction(ETR)theory is a new fundamental theory guiding the design of synthetic routes.It analyses problems from a brand-new perspective of element circulation,decomposing the factors affecting synthetic efficiency into three elements:element sources,driving force,and output.Different from the retrosynthetic analysis method and the atom economy theory,the ETR theory places more emphasis on examining the problem as a whole and comprehensively considering various factors involved in industrial applications.This perspective intends to elaborate on the scientific connotation of the ETR theory and explore its characteristics by discussing the practical application cases. 展开更多
关键词 Element Transfer Reaction theory Element source Driving force OUTPUT Energy conservation Atom economy
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Galerkin-Vlasov approach for bending analysis of flexoelectric doubly-curved sandwich nanoshells with piezoelectric/FGP/piezoelectric layers using the nonlocal strain theory 被引量:1
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作者 Tran Van Ke Do Van Thom +2 位作者 Nguyen Thai Dung Nguyen Van Chinh Phung Van Minh 《Acta Mechanica Sinica》 2025年第2期7-40,共34页
Flexoelectricity refers to the link between electrical polarization and strain gradient fields in piezoelectric materials,particularly at the nano-scale.The present investigation aims to comprehensively focus on the s... Flexoelectricity refers to the link between electrical polarization and strain gradient fields in piezoelectric materials,particularly at the nano-scale.The present investigation aims to comprehensively focus on the static bending analysis of a piezoelectric sandwich functionally graded porous(FGP)double-curved shallow nanoshell based on the flexoelectric effect and nonlocal strain gradient theory.Two coefficients that reduce or increase the stiffness of the nanoshell,including nonlocal and length-scale parameters,are considered to change along the nanoshell thickness direction,and three different porosity rules are novel points in this study.The nanoshell structure is placed on a Pasternak elastic foundation and is made up of three separate layers of material.The outermost layers consist of piezoelectric smart material with flexoelectric effects,while the core layer is composed of FGP material.Hamilton’s principle was used in conjunction with a unique refined higher-order shear deformation theory to derive general equilibrium equations that provide more precise outcomes.The Navier and Galerkin-Vlasov methodology is used to get the static bending characteristics of nanoshells that have various boundary conditions.The program’s correctness is assessed by comparison with published dependable findings in specific instances of the model described in the article.In addition,the influence of parameters such as flexoelectric effect,nonlocal and length scale parameters,elastic foundation stiffness coefficient,porosity coefficient,and boundary conditions on the static bending response of the nanoshell is detected and comprehensively studied.The findings of this study have practical implications for the efficient design and control of comparable systems,such as micro-electromechanical and nano-electromechanical devices. 展开更多
关键词 Analytical solution Flexoelectric effect Nonlocal strain gradient theory Static bending of nanoshell
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Exploring artificial intelligence approaches for predicting synergistic effects of active compounds in traditional Chinese medicine based on molecular compatibility theory 被引量:1
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作者 Yiwen Wang Tong Wu +5 位作者 Xingyu Li Qilan Xu Heshui Yu Shixin Cen Yi Wang Zheng Li 《Chinese Journal of Natural Medicines》 2025年第11期1409-1424,共16页
Due to its synergistic effects and reduced side effects,combination therapy has become an important strategy for treating complex diseases.In traditional Chinese medicine(TCM),the“monarch,minister,assistant,envoy”co... Due to its synergistic effects and reduced side effects,combination therapy has become an important strategy for treating complex diseases.In traditional Chinese medicine(TCM),the“monarch,minister,assistant,envoy”compatibilities theory provides a systematic framework for drug compatibility and has guided the formation of a large number of classic formulas.However,due to the complex compositions and diverse mechanisms of action of TCM,it is difficult to comprehensively reveal its potential synergistic patterns using traditional methods.Synergistic prediction based on molecular compatibility theory provides new ideas for identifying combinations of active compounds in TCM.Compared to resource-intensive traditional experimental methods,artificial intelligence possesses the ability to mine synergistic patterns from multi-omics and structural data,providing an efficient means for modeling and optimizing TCM combinations.This paper systematically reviews the application progress of AI in the synergistic prediction of TCM active compounds and explores the challenges and prospects of its application in modeling combination relationships,thereby contributing to the modernization of TCM theory and methodological innovation. 展开更多
关键词 Molecular compatibility theory Synergy prediction of TCM compounds Molecular drugs combination prediction Artificial intelligence
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问题与回答——Theorizing A New Agenda for Architecture,An Anthology of Architectural Theory,1965~1995一书引起的思考
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作者 张巍 王一平 《华中建筑》 2010年第3期4-6,共3页
内斯比特(KateNesbitt)在她的Theorizing A New Agenda for Architecture,An Anthology of Architectural Theory,1965~1995一书中较为全面地介绍了当代西方建筑理论界所关心的主要问题及其相关的思考。对于这些问题,国内建筑理论界也... 内斯比特(KateNesbitt)在她的Theorizing A New Agenda for Architecture,An Anthology of Architectural Theory,1965~1995一书中较为全面地介绍了当代西方建筑理论界所关心的主要问题及其相关的思考。对于这些问题,国内建筑理论界也有自己的认识。该文通过对两者的比较,试图理清建筑理论的基本意义,那就是提出问题并引起思考。 展开更多
关键词 问题 回答 理论的意义
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Gravitational Collapse and Expansion in the Newton Theory and General Relativity
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作者 Valery V. Vasiliev Leonid V. Fedorov 《Journal of Modern Physics》 2025年第2期294-309,共16页
The paper is devoted to the study of the gravitational collapse within the framework of the spherically symmetric problem in the Newton theory and general relativity on the basis of the pressure-free model of the cont... The paper is devoted to the study of the gravitational collapse within the framework of the spherically symmetric problem in the Newton theory and general relativity on the basis of the pressure-free model of the continuum. In application to the Newton gravitation theory, the analysis consists of three stages. First, we assume that the gravitational force is determined by the initial sphere radius and constant density and does not change in the process of the sphere collapse. The obtained analytical solution allows us to find the collapse time in the first approximation. Second, we construct the step-by-step process in which the gravitational force at a given time moment depends on the current sphere radius and density. The obtained numerical solution specifies the collapse time depending on the number of steps. Third, we find the exact value of the collapse time which is the limit of the step-by-step solutions and study the collapse and the expansion processes in the Newton theory. In application to general relativity, we use the space model corresponding to the special four-dimensional space which is Euclidean with respect to space coordinates and Riemannian with respect to the time coordinate only. The obtained solution specifies two possible scenarios. First, sphere contraction results in the infinitely high density with the finite collapse time, which does not coincide with the conventional result corresponding to the Schwarzschild geometry. Second, sphere expansion with the velocity which increases with a distance from the sphere center and decreases with time. 展开更多
关键词 Gravitational Collapse Newton Gravitation theory General Relativity
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Decoding the architectural theory
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作者 Gu Mengchao 《Engineering Sciences》 EI 2008年第2期32-36,共5页
Starting from the illustration of the definition and concept of the architectural theory, the author established his unique understanding about the framework of the architectural theory and the innovation of the archi... Starting from the illustration of the definition and concept of the architectural theory, the author established his unique understanding about the framework of the architectural theory and the innovation of the architectural theory underlined by Chinese characteristics. 展开更多
关键词 architectural theory framework of architectural theory starting point and destination of architectural theory innovation of architectural theory
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