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On an Axiomatic Foundation for a Theory of Everything 被引量:6
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作者 CUI Weicheng 《Journal of Philosophy Study》 2021年第4期241-267,共27页
Whether a unified theory of everything(TOE)is possible or not is a philosophical question and yes or no can be chosen in a two-valued logic system.Currently the two schools are in conflict with each other.Based on the... Whether a unified theory of everything(TOE)is possible or not is a philosophical question and yes or no can be chosen in a two-valued logic system.Currently the two schools are in conflict with each other.Based on the relativity of simultaneity axiom proposed in this paper,the present author suggests to use a midway philosophy to replace the present materialist philosophy for modern sciences;then this conflict together with many other conflicts among different theories such as classical mechanics(CM),general relativity(GR),and quantum mechanics(QM)can be solved and a unified theory of everything for the world we can observe can be constructed.In this paper,the axiomatic foundation for a TOE is proposed which contains six fundamental axioms.Various problems related to these foundational issues are discussed.It is hoped that the present paper might show a new promise and a new direction for TOE which would be helpful for the further development of modern sciences. 展开更多
关键词 AXIOM mind-body problem the demarcation problem cause-effect law theory of everything(TOE)
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The Three Postulates of the Theory of Everything 被引量:1
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作者 Ding-Yu Chung 《Journal of Modern Physics》 2016年第7期642-655,共14页
The three postulates of the posited dynamic and reversible theory of everything are: 1) the oscil-lating M-theory postulate for the oscillating matter structure, 2) the digital transitional Higgs-reversed Higgs fields... The three postulates of the posited dynamic and reversible theory of everything are: 1) the oscil-lating M-theory postulate for the oscillating matter structure, 2) the digital transitional Higgs-reversed Higgs fields postulate for the digital space structure, and 3) the reversible multiverse post-ulate for all physical laws and phenomena. The posited theory of everything based on the three postulates explains cosmology, the composition (baryonic matter, dark matter, and dark energy) in the universe, the periodic table of elementary particles (quarks, leptons, and bosons), the galaxy evolution, superconductivity, black hole, thermodynamic, and quantum mechanics. Oscillating M-theory is derived from oscillating membrane-string-particle whose space-time dimension number oscillates between 11D and 10D and between 10D and 4D. Space-time dimension number between 10 and 4 decreases with decreasing speed of light, decreasing vacuum energy, and in-creasing rest mass. The digital transitional Higgs-reversed Higgs fields are derived from digital attachment-detachment spaces which couple to particles. Under spontaneous symmetry breaking, the coupling of massless particle to zero-energy attachment space (the space for mass) produces the transitional nonzero-energy Higgs field-particle composite which under spontaneous symmetry restoring produces massive particle on zero-energy attachment space with the longitudinal component. The opposite of attachment space is detachment space as the space for kinetic energy and the nonzero-energy reverse Higgs field. The combination of n units of attachment space (de-noted as 1) and n units of detachment space (denoted as 0) brings about the three digital structures: binary partition space (1)<sub>n</sub>(0)<sub>n</sub>, miscible space (1 + 0)<sub>n</sub>, and binary lattice space (1 0)<sub>n</sub> to account for quantum mechanics, special relativity, and the force fields, respectively. In the third postulate, all physical laws and phenomena are permanently reversible in the multiverse, and temporary irreversible entropy increase is allowed. Our universe is an asymmetrical dual posi-tive-energy-negative-energy universe where the positive-energy universe on attachment space absorbed the interuniversal void on detachment space to result in the combination of attachment space and detachment space, while the negative-energy universe did not absorb the interuniversal void, resulting in temporary irreversible entropy increase through reversibility breaking, sym-metry violation, and low entropy beginning. Guided by the reversible negative-energy universe, our dual universe is a globally reversible cyclic dual universe. 展开更多
关键词 The theory of everything M-theory Higgs Field Reverse Higgs Field MULTIVERSE COSMOLOGY Matter Structure Space Structure Entropy THERMODYNAMIC Cyclic Universe Interuniversal Void
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Tales de Miletus,Hegel,and the Theory of Everything
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作者 Alfredo de Oliveira Moraes 《Journal of Philosophy Study》 2023年第1期28-35,共8页
The author takes how focus of your reflection the no achievement of the Theory of Everything in the Whole,he indicates that the cause of that frustrated attempts it is the basis of construction of the thought used to,... The author takes how focus of your reflection the no achievement of the Theory of Everything in the Whole,he indicates that the cause of that frustrated attempts it is the basis of construction of the thought used to,lay emphasis on the inadequacy of the thought supported in the metaphysical from material basis,with roots in Tales de Miletus,in ruling to find a solution,and he presents the metaphysical from relational basis,proto-enunciated in the Hegel’s thought,like a possible foundation to think what can be capable to apprehend the effectiveness reality in the flow of its happen,so in the scope of the existence of phenomena infra nanos,so well,in the hyper macros events. 展开更多
关键词 METAPHYSICAL theory of everything Hegelian dialectic
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The Theory of Everything as the Reversibility Theory
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作者 Ding-Yu Chung 《Journal of Modern Physics》 2015年第13期1820-1832,共13页
In the posited reversibility theory, 1) all physical laws and phenomena are permanently reversible, 2) all physical laws are derived from the reversible M-theory (extension of string theory) in the reversible multiver... In the posited reversibility theory, 1) all physical laws and phenomena are permanently reversible, 2) all physical laws are derived from the reversible M-theory (extension of string theory) in the reversible multiverse, and 3) temporary irreversible entropy increase is allowed through reversibility breaking, symmetry breaking, and low entropy beginning. Dealing with all physical laws and phenomena, the reversibility theory is the theory of everything, including thermodynamic, cosmology, the composition (baryonic matter, dark matter, and dark energy) in the universe, the periodic table of all elementary particles, the galaxy evolution, superconductivity, and black hole. In the reversible M-theory, space-time dimension number oscillates between 11D (space-time dimension) and 10D and between 10D and 4D. The reversible M-theory includes 11D membrane, 10D string, and variable D particle. Space-time dimension number between 10 and 4 decreases with decreasing speed of light, decreasing vacuum energy, and increasing rest mass. In our dual universe of positive-negative energy universe, the reversible oscillation between 10D with and 4D in the negative energy universe without kinetic energy is the reversible cyclic fractionalization-condensation for the reversible cyclic expansion-contraction of the universe. Without kinetic energy, the individual particles have no individual momenta for entropy increase. The negative energy universe is the locally reversible universe for dark energy. In the positive energy universe where we live, the absorption of the interuniversal void forced the direct transformation from 10D to 4D as the inflation followed by the Big Bang, and created kinetic energy that provided individual momenta for individual particles to produce irreversible entropy increase, resulting in the reversibility breaking of the reversible oscillation. The positive energy universe is the locally irreversible universe. The dual universe as a whole is reversible guided by the reversible negative energy universe. As a result, the irreversible positive energy universe with the irreversible entropy increase is temporary, and will disappear. 展开更多
关键词 The theory of everything REVERSIBILITY theory Entropy Thermodynamic Cyclic Universe MULTIVERSE Interuniversal VOID M-theory Cosmology String theory
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Towards a Unified Theory of Everything: Integrating Discrete Time Evolution and Classical-Quantum Dynamics in the Advanced Observer Model (AOM)
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作者 Joseph H. C. Wong 《Journal of Quantum Information Science》 2024年第4期196-233,共38页
This paper introduces the Advanced Observer Model (AOM), a novel framework that integrates classical mechanics, quantum mechanics, and relativity through the observer’s role in constructing reality. Central to the AO... This paper introduces the Advanced Observer Model (AOM), a novel framework that integrates classical mechanics, quantum mechanics, and relativity through the observer’s role in constructing reality. Central to the AOM is the Static Configuration/Dynamic Configuration (SC/DC) conjugate, which examines physical systems through the interaction between static spatial configurations and dynamic quantum states. The model introduces a Constant Frame Rate (CFR) to quantize time perception, providing a discrete model for time evolution in quantum systems. By modifying the Schrödinger equation with CFR, the AOM bridges quantum and classical physics, offering a unified interpretation where classical determinism and quantum uncertainty coexist. A key feature of the AOM is its energy scaling model, where energy grows exponentially with spatial dimensionality, following the relationshipE∝(π)n. This dimensional scaling connects the discrete time perception of the observer with both quantum and classical energy distributions, providing insights into the nature of higher-dimensional spaces. Additionally, the AOM posits that spacetime curvature arises from quantum interactions, shaped by the observer’s discrete time perception. The model emphasizes the observer’s consciousness as a co-creator of reality, offering new approaches to understanding the quantum-classical transition. While speculative, the AOM opens new avenues for addressing foundational questions in quantum mechanics, relativity, dimensionality, and the nature of reality. 展开更多
关键词 Quantum Mechanics Schrödinger Equation Constant Frame Rate (CFR) Advanced Observer Model (AOM) Relativistic Physics Classical-Quantum Transition Wave Function Discrete Time Evolution Spacetime Geometry Unified theory Quantum-Classical Unification Observer-Dependent Reality Energy Scaling
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Effect of extended nursing based on self-efficacy theory on the anxiety of patients with intertrochanteric fracture
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作者 You-Mei Yao Xue-Yun Shao +1 位作者 Lin-Li Sha Lin-Lin Qian 《World Journal of Psychiatry》 2025年第2期92-99,共8页
BACKGROUND Extended care based on self-efficacy theory to elderly patients with intertrochanteric fractures will provide data reference to optimize the care plan of these patients,reduce patients’concurrent mental di... BACKGROUND Extended care based on self-efficacy theory to elderly patients with intertrochanteric fractures will provide data reference to optimize the care plan of these patients,reduce patients’concurrent mental diseases,and improve prognosis.AIM To analyze the value of extended nursing based on the self-efficacy theory in older patients with intertrochanteric fractures.METHODS Older patients with intertrochanteric fractures(n=88)admitted to our hospital between January 2021 and December 2024 were randomly divided into two groups-the control group(n=44,routine nursing)and the observation group(n=44,extended nursing)-via balloting and treated for 12 weeks.The mental state,pain severity,limb function,and self-nursing ability of all patients before and after nursing were analyzed.RESULTS After nursing,the Hamilton Anxiety Scale and General Self-Efficacy Scale scores of patients in the two groups improved.Notably,Hamilton Anxiety Scale and General Self-Efficacy Scale scores in the observation group were lower and higher,respectively,than those in the control group(P<0.05).The pain severity in the observation group(2.64±0.22)was lower than that in the control group(2.85±0.41)(P<0.05).The recovery rate of limb function was higher in the observation group than in the control group(P<0.05).In addition,the self-nursing ability scores of the patients in both groups increased,with a significantly higher score in the observation group(P<0.05).CONCLUSION Extended nursing based on the self-efficacy theory can significantly improve mental state,relieve pain,and promote the recovery of limb function and self-nursing ability in older patients with intertrochanteric fractures. 展开更多
关键词 Self-efficacy theory Extended nursing Intertrochanteric fractures Mental health CLINIC
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Timing theory integrated nursing combined behavior change integrated theory of nursing on primiparous influence 被引量:2
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作者 Yan-Xia He Yang Lv +2 位作者 Ting-Ting Lan Fang Deng Yuan-Yuan Zhang 《World Journal of Clinical Cases》 SCIE 2024年第2期293-301,共9页
BACKGROUND The comprehension and utilization of timing theory and behavior change can offer a more extensive and individualized provision of support and treatment alternatives for primipara.This has the potential to e... BACKGROUND The comprehension and utilization of timing theory and behavior change can offer a more extensive and individualized provision of support and treatment alternatives for primipara.This has the potential to enhance the psychological well-being and overall quality of life for primipara,while also furnishing healthcare providers with efficacious interventions to tackle the psychological and physiological obstacles encountered during the stages of pregnancy and postpartum.AIM To explore the effect of timing theory combined with behavior change on selfefficacy,negative emotions and quality of life in patients with primipara.METHODS A total of 80 primipara cases were selected and admitted to our hospital between August 2020 and May 2022.These cases were divided into two groups,namely the observation group and the control group,with 40 cases in each group.The nursing interventions differed between the two groups,with the control group receiving routine nursing and the observation group receiving integrated nursing based on the timing theory and behavior change.The study aimed to compare the pre-and post-nursing scores of Chinese Perceived Stress Scale(CPSS),Edinburgh Postpartum Depression Scale(EPDS),Self-rating Anxiety Scale(SAS),breast milk knowledge,self-efficacy,and SF-36 quality of life in both groups.RESULTS After nursing,the CPSS,EPDS,and SAS scores of the two groups was significantly lower than that before nursing,and the CPSS,EPDS,and SAS scores of the observation group was significantly lower than that of the control group(P=0.002,P=0.011,and P=0.001 respectively).After nursing,the breastfeeding knowledge mastery,selfefficacy,and SF-36 quality of life scores was significantly higher than that before nursing,and the breastfeeding knowledge mastery(P=0.013),self-efficacy(P=0.008),and SF-36 quality of life(P=0.011)scores of the observation group was significantly higher than that of the control group.CONCLUSION The integration of timing theory and behavior change integrated theory has been found to be an effective approach in alleviating negative mood and stress experienced by primipara individuals,while also enhancing their selfefficacy and overall quality of life.This study focuses on the key concepts of timing theory,behavior change,primipara individuals,negative mood,and quality of life. 展开更多
关键词 Timing theory Behavior change PRIMIPARA Bad mood Quality of life
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Systems Theory-Driven Framework for AI Integration into the Holistic Material Basis Research of Traditional Chinese Medicine 被引量:1
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作者 Jingqi Zeng Xiaobin Jia 《Engineering》 SCIE EI CAS CSCD 2024年第9期28-50,共23页
This paper introduces a systems theory-driven framework to integration artificial intelligence(AI)into traditional Chinese medicine(TCM)research,enhancing the understanding of TCM’s holistic material basis while adhe... This paper introduces a systems theory-driven framework to integration artificial intelligence(AI)into traditional Chinese medicine(TCM)research,enhancing the understanding of TCM’s holistic material basis while adhering to evidence-based principles.Utilizing the System Function Decoding Model(SFDM),the research progresses through define,quantify,infer,and validate phases to systematically explore TCM’s material basis.It employs a dual analytical approach that combines top-down,systems theory-guided perspectives with bottom-up,elements-structure-function methodologies,provides comprehensive insights into TCM’s holistic material basis.Moreover,the research examines AI’s role in quantitative assessment and predictive analysis of TCM’s material components,proposing two specific AIdriven technical applications.This interdisciplinary effort underscores AI’s potential to enhance our understanding of TCM’s holistic material basis and establishes a foundation for future research at the intersection of traditional wisdom and modern technology. 展开更多
关键词 Artificial intelligence Systems theory Traditional Chinese medicine Material basis BOTTOM-UP
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Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory 被引量:1
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作者 Yang Su Ze-Yu Li +3 位作者 Li-Le Liu Guo-Xiang Dong Xiao-Bao Wang Yong-Jing Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期198-207,共10页
Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pair... Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data. 展开更多
关键词 Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution
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Enhancing the resolution of sparse rock property measurements using machine learning and random field theory 被引量:1
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作者 Jiawei Xie Jinsong Huang +3 位作者 Fuxiang Zhang Jixiang He Kaifeng Kang Yunqiang Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期3924-3936,共13页
The travel time of rock compressional waves is an essential parameter used for estimating important rock properties,such as porosity,permeability,and lithology.Current methods,like wireline logging tests,provide broad... The travel time of rock compressional waves is an essential parameter used for estimating important rock properties,such as porosity,permeability,and lithology.Current methods,like wireline logging tests,provide broad measurements but lack finer resolution.Laboratory-based rock core measurements offer higher resolution but are resource-intensive.Conventionally,wireline logging and rock core measurements have been used independently.This study introduces a novel approach that integrates both data sources.The method leverages the detailed features from limited core data to enhance the resolution of wireline logging data.By combining machine learning with random field theory,the method allows for probabilistic predictions in regions with sparse data sampling.In this framework,12 parameters from wireline tests are used to predict trends in rock core data.The residuals are modeled using random field theory.The outcomes are high-resolution predictions that combine both the predicted trend and the probabilistic realizations of the residual.By utilizing unconditional and conditional random field theories,this method enables unconditional and conditional simulations of the underlying high-resolution rock compressional wave travel time profile and provides uncertainty estimates.This integrated approach optimizes the use of existing core and logging data.Its applicability is confirmed in an oil project in West China. 展开更多
关键词 Wireline logs Core characterization Compressional wave travel time Machine learning Random field theory
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Transient response of doubly-curved bio-inspired composite shells resting on viscoelastic foundation subject to blast load using improved first-order shear theory and isogeometric approach 被引量:1
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作者 Thuy Tran Thi Thu Tu Nguyen Anh +1 位作者 Hue Nguyen Thi Hong Nguyen Thi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期171-193,共23页
Investigating natural-inspired applications is a perennially appealing subject for scientists. The current increase in the speed of natural-origin structure growth may be linked to their superior mechanical properties... Investigating natural-inspired applications is a perennially appealing subject for scientists. The current increase in the speed of natural-origin structure growth may be linked to their superior mechanical properties and environmental resilience. Biological composite structures with helicoidal schemes and designs have remarkable capacities to absorb impact energy and withstand damage. However, there is a dearth of extensive study on the influence of fiber redirection and reorientation inside the matrix of a helicoid structure on its mechanical performance and reactivity. The present study aimed to explore the static and transient responses of a bio-inspired helicoid laminated composite(B-iHLC) shell under the influence of an explosive load using an isomorphic method. The structural integrity of the shell is maintained by a viscoelastic basis known as the Pasternak foundation, which encompasses two coefficients of stiffness and one coefficient of damping. The equilibrium equations governing shell dynamics are obtained by using Hamilton's principle and including the modified first-order shear theory,therefore obviating the need to employ a shear correction factor. The paper's model and approach are validated by doing numerical comparisons with respected publications. The findings of this study may be used in the construction of military and civilian infrastructure in situations when the structure is subjected to severe stresses that might potentially result in catastrophic collapse. The findings of this paper serve as the foundation for several other issues, including geometric optimization and the dynamic response of similar mechanical structures. 展开更多
关键词 Blast load Modified first-order shear theory Biological composite structures
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Density functional theory study of B- and Si-doped carbons and their adsorption interactions with sulfur compounds
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作者 Peng Guo Hong Zhang +1 位作者 Shuliang Dong Libao An 《Carbon Energy》 SCIE EI CAS CSCD 2024年第2期195-208,共14页
Understanding the adsorption interactions between carbon materials and sulfur compounds has far-reaching impacts,in addition to their well-known important role in energy storage and conversion,such as lithium-ion batt... Understanding the adsorption interactions between carbon materials and sulfur compounds has far-reaching impacts,in addition to their well-known important role in energy storage and conversion,such as lithium-ion batteries.In this paper,properties of intrinsic B or Si single-atom doped,and B-Si codoped graphene(GR)and graphdiyne(GDY)were investigated by using density functional theory-based calculations,in which the optimal doping configurations were explored for potential applications in adsorbing sulfur compounds.Results showed that both B or Si single-atom doping and B-Si codoping could substantially enhance the electron transport properties of GR and GDY,improving their surface activity.Notably,B and Si atoms displayed synergistic effects for the codoped configurations,where B-Si codoped GR/GDY exhibited much better performance in the adsorption of sulfurcontaining chemicals than single-atom doped systems.In addition,results demonstrated that,after B-Si codoping,the adsorption energy and charge transfer amounts of GDY with sulfur compounds were much larger than those of GR,indicating that B-Si codoped GDY might be a favorable material for more effectively interacting with sulfur reagents. 展开更多
关键词 ADSORPTION density functional theory DOPING graphdiyne GRAPHENE sulfur compounds
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Anti-rollover Artificial Potential Field Motion Planning Method of an Autonomous Heavy Truck Optimised by Game Theory
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作者 Zhilin Jin Shaowei He 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第5期523-542,共20页
Anti-rollover is a critical factor to consider when planning the motion of autonomous heavy trucks.This paper proposed a method for autonomous heavy trucks to generate a path that avoids collisions and minimizes rollo... Anti-rollover is a critical factor to consider when planning the motion of autonomous heavy trucks.This paper proposed a method for autonomous heavy trucks to generate a path that avoids collisions and minimizes rollover risk.The corresponding rollover index is deduced from a 5-DOF heavy truck dynamic model that includes longitudinal motion,lateral motion,yaw motion,sprung mass roll motion,unsprung mass roll motion,and an anti-rollover artificial potential field(APF)is proposed based on this.The motion planning method,which is based on model predictive control(MPC),combines trajectory tracking,anti-rollover APF,and the improved obstacle avoidance APF and considers the truck dynamics constraints,obstacle avoidance,and anti-rollover.Furthermore,by using game theory,the coefficients of the two APF functions are optimised,and an optimal path is planned.The effectiveness of the optimised motion planning method is demonstrated in a variety of scenarios.The results demonstrate that the optimised motion planning method can effectively and efficiently avoid collisions and prevent rollover. 展开更多
关键词 Autonomous heavy truck Motion planning Anti-rollover Artificial potential field Game theory
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Langmuir-Schaefer Film Investigation and Density Functional Theory Band Gap Calculations of Calix[n]arene-Para-Aminobenzoic Acid for Drug Nanosensor Application
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作者 WONG Yeong Yi F L Supian +2 位作者 A Radzwan M Musa N F N Abd Karim 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1311-1318,共8页
Calix[n]arenes was utilized to detect PABA,the primary sunscreen component.This study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density ... Calix[n]arenes was utilized to detect PABA,the primary sunscreen component.This study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density functional theory(DFT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various substrates.Based on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:1.All of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),Fourier-transform infrared spectroscopy(FTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHNS).The band gap reduction obtained in the DFT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and PABA.The sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping capacity.The outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications. 展开更多
关键词 calix[n]arenes band gap density functional theory Langmuir-Schaefer PABA sensor
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Island biogeography theory and the habitat heterogeneity jointly explain global patterns of Rhododendron diversity
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作者 Yanwei Guan Yongru Wu +4 位作者 Zheng Cao Zhifeng Wu Fangyuan Yu Haibin Yu Tiejun Wang 《Plant Diversity》 SCIE CAS CSCD 2024年第5期565-574,共10页
Mountain biodiversity is of great importance to biogeography and ecology.However,it is unclear what ecological and evolutionary processes best explain the generation and maintenance of its high levels of species diver... Mountain biodiversity is of great importance to biogeography and ecology.However,it is unclear what ecological and evolutionary processes best explain the generation and maintenance of its high levels of species diversity.In this study,we determined which of six common hypotheses(e.g.,climate hypotheses,habitat heterogeneity hypothesis and island biogeography theory)best explain global patterns of species diversity in Rhododendron.We found that Rhododendron diversity patterns were most strongly explained by proxies of island biogeography theory(i.e.,mountain area)and habitat heterogeneity(i.e.,elevation range).When we examined other relationships important to island biogeography theory,we found that the planimetric area and the volume of mountains were positively correlated with the Rhododendron diversity,whereas the‘mountains-to-mainland’distance was negatively correlated with Rhododendron diversity and shared species.Our findings demonstrate that Rhododendron diversity can be explained by island biogeography theory and habitat heterogeneity,and mountains can be regarded as islands which supported island biogeography theory. 展开更多
关键词 Mountain biodiversity RHODODENDRON Island biogeography theory Habitat heterogeneity Biogeographical hypotheses Plant diversity
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Optimized numerical density functional theory calculation of rotationally symmetric jellium model systems
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作者 Guangdi Zhang Li Mao Hongxing Xu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期349-355,共7页
In real space density functional theory calculations,the effective potential depends on the electron density,requiring self-consistent iterations,and numerous integrals at each step,making the process time-consuming.I... In real space density functional theory calculations,the effective potential depends on the electron density,requiring self-consistent iterations,and numerous integrals at each step,making the process time-consuming.In our research,we propose an optimization method to expedite density functional theory(DFT)calculations for systems with large aspect ratios,such as metallic nanorods,nanowires,or scanning tunneling microscope tips.This method focuses on employing basis set to expand the electron density,Coulomb potential,and exchange-correlation potential.By precomputing integrals and caching redundant results,this expansion streamlines the integration process,significantly accelerating DFT computations.As a case study,we have applied this optimization to metallic nanorod systems of various radii and lengths,obtaining corresponding ground-state electron densities and potentials. 展开更多
关键词 density functional theory basis set integrals precomputation nanorod
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A density functional theory study of polarons on different TiO_(2) surfaces
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作者 SHI Zhiqun GONG Xueqing 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第12期1877-1888,I0011-I0013,共15页
Polarons are widely considered to play a crucial role in the charge transport and photocatalytic performance of materials,but the mechanisms of their formation and the underlying driving factors remain a matter of con... Polarons are widely considered to play a crucial role in the charge transport and photocatalytic performance of materials,but the mechanisms of their formation and the underlying driving factors remain a matter of controversy.This study delves into the formation of polarons in different crystalline forms of TiO_(2) and their connection with the materials'structure.By employing density functional theory calculations with on-site Coulomb interaction correction(DFT+U),we provide a detailed analysis of the electronic polarization behavior in the anatase and rutile forms of TiO_(2).We focus on the polarization properties of defect-induced and photoexcited excess electrons on various TiO_(2) surfaces.The results reveal that the defect electrons can form small polarons on the anatase TiO_(2)(101)surface,while on the rutile TiO_(2)(110)surface,both small and large polarons(hybrid-state polarons)are formed.Photoexcited electrons are capable of forming both small and large polarons on the surfaces of both crystal types.The analysis indicates that the differences in polaron distribution are primarily determined by the intrinsic properties of the crystals;the structural and symmetry differences between anatase and rutile TiO_(2) lead to the distinct polaron behaviors.Further investigation suggests that the polarization behavior of defect electrons is also related to the arrangement of electron orbitals around the Ti atoms,while the polarization of photoexcited electrons is mainly facilitated by the lattice distortions.These findings elucidate the formation mechanisms of different types of polarons and may contribute to understanding the performance of TiO_(2)in different fields. 展开更多
关键词 POLARON surface defect PHOTOEXCITATION TiO_(2) density functional theory
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Comparative study on phase transition behaviors of fractional molecular field theory and random-site Ising model
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作者 刘婷玉 赵薇 +3 位作者 王涛 安小冬 卫来 黄以能 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期536-541,共6页
Fractional molecular field theory(FMFT)is a phenomenological theory that describes phase transitions in crystals with randomly distributed components,such as the relaxor-ferroelectrics and spin glasses.In order to ver... Fractional molecular field theory(FMFT)is a phenomenological theory that describes phase transitions in crystals with randomly distributed components,such as the relaxor-ferroelectrics and spin glasses.In order to verify the feasibility of this theory,this paper fits it to the Monte Carlo simulations of specific heat and susceptibility versus temperature of two-dimensional(2D)random-site Ising model(2D-RSIM).The results indicate that the FMFT deviates from the 2D-RSIM significantly.The main reason for the deviation is that the 2D-RSIM is a typical system of component random distribution,where the real order parameter is spatially heterogeneous and has no symmetry of space translation,but the basic assumption of FMFT means that the parameter is spatially uniform and has symmetry of space translation. 展开更多
关键词 phase transition molecular field theory Ising model Monte Carlo
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Retrospective and prospective review of the generalized nonlinear strength theory for geomaterials
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作者 Shunchuan Wu Jiaxin Wang +3 位作者 Shihuai Zhang Shigui Huang Lei Xia Qianping Zhao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第8期1767-1787,共21页
Strength theory is the basic theory for calculating and designing the strength of engineering materials in civil,hydraulic,mechanical,aerospace,military,and other engineering disciplines.Therefore,the comprehensive st... Strength theory is the basic theory for calculating and designing the strength of engineering materials in civil,hydraulic,mechanical,aerospace,military,and other engineering disciplines.Therefore,the comprehensive study of the generalized nonlinear strength theory(GNST)of geomaterials has significance for the construction of engineering rock strength.This paper reviews the GNST of geomaterials to demonstrate the research status of nonlinear strength characteristics of geomaterials under complex stress paths.First,it systematically summarizes the research progress of GNST(classical and empirical criteria).Then,the latest research the authors conducted over the past five years on the GNST is introduced,and a generalized three-dimensional(3D)nonlinear Hoek‒Brown(HB)criterion(NGHB criterion)is proposed for practical applications.This criterion can be degenerated into the existing three modified HB criteria and has a better prediction performance.The strength prediction errors for six rocks and two in-situ rock masses are 2.0724%-3.5091%and 1.0144%-3.2321%,respectively.Finally,the development and outlook of the GNST are expounded,and a new topic about the building strength index of rock mass and determining the strength of in-situ engineering rock mass is proposed.The summarization of the GNST provides theoretical traceability and optimization for constructing in-situ engineering rock mass strength. 展开更多
关键词 rock mechanics rock mass strength strength theory failure criterion Hoek-Brown criterion intermediate principal stress deviatoric plane smoothness and convexity
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Why the abnormal phenomena of D-band center theory exist?A new BASED theory for surface catalysis and chemistry
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作者 Zelong Qiao Run Jiang +1 位作者 Jimmy Yun Dapeng Cao 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期44-53,共10页
Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with th... Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with the continuous development of material systems and modification strategies,researchers have gradually found that D-band center theory is usually effective for large metal particle systems,but for small metal particle systems or semiconductors,such as single atom systems,the opposite conclusion to the D-band center theory is often obtained.To solve the issue above,here we propose a bonding and anti-bonding orbitals stable electron intensity difference(BASED)theory for surface chemistry.The newly-proposed BASED theory can not only successfully explain the abnormal phenomena of D-band center theory,but also exhibits a higher accuracy for prediction of adsorption energy and bond length of intermediates on active sites.Importantly,a new phenomenon of the spin transition state in the adsorption process is observed based on the BASED theory,where the active center atom usually yields an unstable high spin transition state to enhance its adsorption capability in the adsorption process of intermediates when their distance is about 2.5Å.In short,the BASED theory can be considered as a general principle to understand catalytic mechanism of intermediates on surfaces. 展开更多
关键词 Surface chemistry Surface catalysis D-band center theory Bonding orbital Anti-bonding orbital
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