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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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A symmetric substructuring method for analyzing the natural frequencies of conical origami structures
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作者 Chenhao Lu Yao Chen +2 位作者 Weiying Fan Jian Feng Pooya Sareh 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期203-210,共8页
Conical origami structures are characterized by their substantial out-of-plane stiffness and energy-absorptioncapacity.Previous investigations have commonly focused on the static characteristics of these lightweight s... Conical origami structures are characterized by their substantial out-of-plane stiffness and energy-absorptioncapacity.Previous investigations have commonly focused on the static characteristics of these lightweight struc-tures.However,the efficient analysis of the natural vibrations of these structures is pivotal for designing conicalorigami structures with programmable stiffness and mass.In this paper,we propose a novel method to analyzethe natural vibrations of such structures by combining a symmetric substructuring method(SSM)and a gener-alized eigenvalue analysis.SSM exploits the inherent symmetry of the structure to decompose it into a finiteset of repetitive substructures.In doing so,we reduce the dimensions of matrices and improve computationalefficiency by adopting the stiffness and mass matrices of the substructures in the generalized eigenvalue analysis.Finite element simulations of pin-jointed models are used to validate the computational results of the proposedapproach.Moreover,the parametric analysis of the structures demonstrates the influences of the number of seg-ments along the circumference and the radius of the cone on the structural mass and natural frequencies of thestructures.Furthermore,we present a comparison between six-fold and four-fold conical origami structures anddiscuss the influence of various geometric parameters on their natural frequencies.This study provides a strategyfor efficiently analyzing the natural vibration of symmetric origami structures and has the potential to contributeto the efficient design and customization of origami metastructures with programmable stiffness. 展开更多
关键词 Natural structural vibration Origami design Group theory Symmetric substructuring method(SSM) Generalized eigenvalue analysis
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The Tension Cosmology, Largest Cosmic Structures and Explosions of Supernovae from SST
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作者 Sylwester Kornowski 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1029-1044,共16页
Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter lea... Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter leads to the disagreement in the galaxy clustering amplitude, quantified by the parameter S8. Within the same model we described the Hubble tension. We described also the mechanism that transforms the gravitational collapse into an explosion—it concerns the dynamics of virtual fields that lead to dark energy. Our calculations concern the Type Ia supernovae and the core-collapse supernovae. We calculated the quantized masses of the progenitors of supernovae, emitted total energy during explosion, and we calculated how much of the released energy was transferred to neutrinos. Value of the speed of sound in the strongly interacting matter measured at the LHC confirms that presented here model is correct. Our calculations show that the Universe is cyclic. 展开更多
关键词 Scale-Symmetric theory Tension Cosmology Coupling Constants Parameters σ8 and S8 Largest Cosmic structures Dark Energy Supernova Explosion Cyclic Universe
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The Axiology of Consciousness in Mocombeian Consciousness Field Theory
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作者 Paul C.Mocombe 《Philosophy Study》 2024年第4期168-185,共18页
This work explores the axiology of consciousness in Mocombe’s consciousness field in the material world.The paper critically assesses Mocombe’s consciousness field theory(CFT)within the larger body of contemporary o... This work explores the axiology of consciousness in Mocombe’s consciousness field in the material world.The paper critically assesses Mocombe’s consciousness field theory(CFT)within the larger body of contemporary ontological debates regarding the nature,origin,and constitution of consciousness in the universe.The work goes on to highlight the manifestation of Mocombe’s consciousness field in the material resource framework that is the earth,and the nature and origins of ethics and values. 展开更多
关键词 structuration theory phenomenological structuralism structure/agency mythopraxis quantum mechanics social class language game Haitian epistemology Haitian/Vilokan idealism consciousness field theory
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Proof of Concept for a Twin Prime Number Universe Using Set Theory
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作者 John R. Crary 《American Journal of Computational Mathematics》 2024年第3期305-317,共13页
The Fine Structure Constant (eFSC) Model attempts to give a classical definition to a magical number that underlies much of quantum physics. The Fine Structure Constant (α) value equal to 137.03599206 represents a di... The Fine Structure Constant (eFSC) Model attempts to give a classical definition to a magical number that underlies much of quantum physics. The Fine Structure Constant (α) value equal to 137.03599206 represents a dimensionless constant that characterizes the strength of the electromagnetic (EM) interaction between subatomic charged particles. Python-generated property counts for the twin prime force F{139/137} show that the adjusted ratio gives a value of α = 137.036. This implies a mathematical framework underlying this constant is based on twin prime numbers and set theory. This study attempts to demonstrate a proof of concept that a hierarchy of fractional twin prime (αII) forces replicates the quantum nature of the universe and is aligned with the Standard Model of Particle Physics. An expanded eFSC Model demonstrates that twin prime forces and their property sets are mathematically viable substitutes for nuclear reactions, as demonstrated for the Beta-minus decay of neutrons into protons. Most significantly, the positive and negative prime numbers define these nuclear reactants and products as positive or negatively charged ions. Furthermore, the eFSC Model provides new insights regarding the hierarchy of EM forces underlying the quantum nature of the universe. 展开更多
关键词 Fine structure Constant (α) Prime Numbers Set theory Conceptual Model Quantum Physics Light and Matter Beta-Minus Decay
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Research on the Relationship Between Environmental and Economic Coupling Systems in Bohai Bay Area Based on a Vector Autoregression(VAR)Model 被引量:1
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作者 CAO Huimin WANG Ping +2 位作者 ZHANG Surong XU Dongpo TIAN Weijun 《Journal of Ocean University of China》 CAS CSCD 2024年第2期557-566,共10页
This study analyzed the impact of land-based contaminants and tertiary industrial structure on economic development in the selected Bohai Bay area,China.Based on panel data spanning 2011-2020,a vector autoregressive(V... This study analyzed the impact of land-based contaminants and tertiary industrial structure on economic development in the selected Bohai Bay area,China.Based on panel data spanning 2011-2020,a vector autoregressive(VAR)model is used to analyze and forecast the short-run and long-run relationships between three industrial structures,pollutant discharge,and economic development.The results showed that the environmental index had a long-term cointegration relationship with the industrial structure economic index.Per capital chemical oxygen demand(PCOD)and per capita ammonia nitrogen(PNH_(3)N)had a positive impact on delta per capita GDP(dPGDP),while per capita solid waste(PSW),the secondary industry rate(SIR)and delta tertiary industry(dTIR)had a negative impact on dPGDP.The VAR model under this coupling system had stability and credibility.The impulse response results showed that the short-term effect of the coupling system on dPGDP was basically consistent with the Granger causality test results.In addition,variance decomposition was used in this study to predict the long-term impact of the coupling system in the next ten periods(i.e.,ten years).It was found that dTIR had a great impact on dPGDP,with a contribution rate as high as 74.35%in the tenth period,followed by the contribution rate of PCOD up to 3.94%,while the long-term contribution rates of PSW,SIR and PNH3N were all less than 1%.The results show that the government should support the development of the tertiary industry to maintain the vitality of economic development and prevent environmental deterioration. 展开更多
关键词 Bohai Bay area environmental pollution industrial structure cointegration theory VaR model impulse response
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Analysis of the Relationship between Mechanical Properties and Pore Structure of MSW Incineration Bottom Ash Fine Aggregate Concrete after Freeze-Thaw Cycles Based on the Gray Theory
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作者 Peng Zhang Dongsheng Shi +1 位作者 Ping Han Wenchao Jiang 《Journal of Renewable Materials》 SCIE EI 2023年第2期669-688,共20页
The destruction of concrete building materials in severely cold regions of the north is more severely affected by freeze-thaw cycles,and the relationship between the mechanical properties and pore structure of concret... The destruction of concrete building materials in severely cold regions of the north is more severely affected by freeze-thaw cycles,and the relationship between the mechanical properties and pore structure of concrete with fine aggregate from municipal solid waste(MSW)incineration bottom ash after freeze-thaw cycles is analyzed under the degree of freeze-thaw hazard variation.In this paper,the gray correlation method is used to calculate the correlation between the relative dynamic elastic modulus,compressive strength,and microscopic porosity parameters to speculate on the most important factors affecting their changes.The GM(1,1)model was established based on the compressive strength of the waste incineration ash aggregate concrete,the relative error between the simulated and actual values in the model was less than 5%,and the accuracy of the model was level 1,indicating that the GM(1,1)model can well reflect the change in the compressive strength of the MSW incineration bottom ash aggregate concrete during freeze-thaw cycles.Using the gray correlation method,the correlation between the relative dynamic elastic modulus,compressive strength,air content,specific surface area,pore spacing coefficient,and pore average chord length was calculated,and the pore spacing coefficient and pore average chord length were determined to be highly correlated with each other.This determination can help analyze and infer the deterioration mechanism of concrete subject to freeze-thaw cycles.These results can provide a theoretical basis for guiding the engineering practice of concrete with fine aggregates of household bottom ash in the northern cold region. 展开更多
关键词 Municipal solid waste incineration bottom ash ConCRETE gray system theory mechanical properties pore structure
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Optimization of Agricultural Industrial Structure in Changping District of Beijing Based on Grey Relational Analysis
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作者 Haosong LI Rao CHEN 《Asian Agricultural Research》 2024年第4期3-7,共5页
In the economic development of Beijing,although the share of the total amount of agricultural industry in the overall economy is relatively low,it has an important impact on the daily life of residents,social stabilit... In the economic development of Beijing,although the share of the total amount of agricultural industry in the overall economy is relatively low,it has an important impact on the daily life of residents,social stability and the development of other industries.Changping District,as an important agricultural production base of Beijing,its agricultural development has an indispensable strategic significance for the stability and growth of the entire regional economy.Therefore,it is very important to study the structure of agricultural industry in Changping District.Based on the detailed analysis of the agricultural industrial structure of Changping District,this paper uses the grey relation theory to analyze the different industries in the agricultural industrial structure of Changping District,including planting,forestry,animal husbandry,fishery and agricultural,forestry,service industries,in order to reveal the impact of these industries on the agricultural industrial structure of Changping District.Through this study,it comes up with specific and feasible suggestions for the optimization of agricultural industrial structure in Changping District,and provides valuable reference for the agricultural development of other areas in Beijing. 展开更多
关键词 GREY RELaTIon theory Changping DISTRICT aGRICULTURaL INDUSTRIaL structure
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Structural and functional connectivity of the whole brain and subnetworks in individuals with mild traumatic brain injury:predictors of patient prognosis
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作者 Sihong Huang Jungong Han +4 位作者 Hairong Zheng Mengjun Li Chuxin Huang Xiaoyan Kui Jun Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1553-1558,共6页
Patients with mild traumatic brain injury have a diverse clinical presentation,and the underlying pathophysiology remains poorly understood.Magnetic resonance imaging is a non-invasive technique that has been widely u... Patients with mild traumatic brain injury have a diverse clinical presentation,and the underlying pathophysiology remains poorly understood.Magnetic resonance imaging is a non-invasive technique that has been widely utilized to investigate neuro biological markers after mild traumatic brain injury.This approach has emerged as a promising tool for investigating the pathogenesis of mild traumatic brain injury.G raph theory is a quantitative method of analyzing complex networks that has been widely used to study changes in brain structure and function.However,most previous mild traumatic brain injury studies using graph theory have focused on specific populations,with limited exploration of simultaneous abnormalities in structural and functional connectivity.Given that mild traumatic brain injury is the most common type of traumatic brain injury encounte red in clinical practice,further investigation of the patient characteristics and evolution of structural and functional connectivity is critical.In the present study,we explored whether abnormal structural and functional connectivity in the acute phase could serve as indicators of longitudinal changes in imaging data and cognitive function in patients with mild traumatic brain injury.In this longitudinal study,we enrolled 46 patients with mild traumatic brain injury who were assessed within 2 wee ks of injury,as well as 36 healthy controls.Resting-state functional magnetic resonance imaging and diffusion-weighted imaging data were acquired for graph theoretical network analysis.In the acute phase,patients with mild traumatic brain injury demonstrated reduced structural connectivity in the dorsal attention network.More than 3 months of followup data revealed signs of recovery in structural and functional connectivity,as well as cognitive function,in 22 out of the 46 patients.Furthermore,better cognitive function was associated with more efficient networks.Finally,our data indicated that small-worldness in the acute stage could serve as a predictor of longitudinal changes in connectivity in patients with mild traumatic brain injury.These findings highlight the importance of integrating structural and functional connectivity in unde rstanding the occurrence and evolution of mild traumatic brain injury.Additionally,exploratory analysis based on subnetworks could serve a predictive function in the prognosis of patients with mild traumatic brain injury. 展开更多
关键词 cognitive function CROSS-SECTIon FOLLOW-UP functional connectivity graph theory longitudinal study mild traumatic brain injury prediction small-worldness structural connectivity subnetworks whole brain network
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Structure,electronic,and nonlinear optical properties of superalkaline M_(3)O(M=Li,Na)doped cyclo[18]carbon
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作者 刘晓东 卢其亮 罗其全 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期311-317,共7页
Cyclo[18]carbon has received considerable attention thanks to its novel geometric configuration and special electronic structure.Superalkalis have low ionization energy.Doping a superalkali in cyclo[18]carbon is an ef... Cyclo[18]carbon has received considerable attention thanks to its novel geometric configuration and special electronic structure.Superalkalis have low ionization energy.Doping a superalkali in cyclo[18]carbon is an effective method to improve the optical properties of the system because considerable electron transfer occurs.In this paper,the geometry,bonding properties,electronic structure,absorption spectrum,and nonlinear optical(NLO)properties of superalkaline M_(3)O(M=Li,Na)-doped cyclo[18]carbon were studied by using density functional theory.M_(3)O and the C_(18) rings are not coplanar.The C_(18) ring still exhibits alternating long and short bonds.The charge transfer between M_(3)O and C_(18) forms stable[M_(3)O]+[C_(18)]-ionic complexes.C_(18)M_(3)O(M=Li,Na)shows striking optical nonlinearity,i.e.,their first-and second-order hyperpolarizability(βvec andγ||)increase considerably atλ=1907 nm and 1460 nm. 展开更多
关键词 superalkaline doped carbon structure and electronic properties nonlinear optical properties density functional theory(DFT)
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Tailoring local structures of atomically dispersed copper sites for highly selective CO_(2) electroreduction
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作者 Kyung‐Jong Noh Byoung Joon Park +5 位作者 Ying Wang Yejung Choi Sang‐Hoon You Yong‐Tae Kim Kug‐Seung Lee Jeong Woo Han 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期79-90,共12页
Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construc... Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construction of optimal local electronic structures for nitrogen‐coordinated Cu sites(Cu–N_(4))on carbon remains challenging.Here,we synthesized the Cu–N–C catalysts with atomically‐dispersed edge‐hosted Cu–N_(4) sites(Cu–N_(4)C_(8))located in a micropore between two graphitic sheets via a facile method to control the concentration of metal precursor.Edge‐hosted Cu–N_(4)C_(8) catalysts outperformed the previously reported M–N–C catalysts for CO_(2)‐to‐CO conversion,achieving a maximum CO Faradaic efficiency(FECO)of 96%,a CO current density of–8.97 mA cm^(–2) at–0.8 V versus reversible hydrogen electrode(RHE),and over FECO of 90%from–0.6 to–1.0 V versus RHE.Computational studies revealed that the micropore of the graphitic layer in edge‐hosted Cu–N_(4)C_(8) sites causes the d‐orbital energy level of the Cu atom to shift upward,which in return decreases the occupancy of antibonding states in the*COOH binding.This research suggests new insights into tailoring the locally coordinated structure of the electrocatalyst at the atomic scale to achieve highly selective electrocatalytic reactions. 展开更多
关键词 atomic local structure density functional theory electrochemical CO_(2)reduction metal nitrogen‐doped carbon single‐atom catalyst
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Optimal Insurance with Background Risk under the Ambiguity and Belief Heterogeneity Structure
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作者 Xiaohan Wang 《Journal of Applied Mathematics and Physics》 2024年第6期2160-2171,共12页
In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal i... In this paper, we discuss the optimal insurance in the presence of background risk while the insured is ambiguity averse and there exists belief heterogeneity between the insured and the insurer. We give the optimal insurance contract when maxing the insured’s expected utility of his/her remaining wealth under the smooth ambiguity model and the heterogeneous belief form satisfying the MHR condition. We calculate the insurance premium by using generalized Wang’s premium and also introduce a series of stochastic orders proposed by [1] to describe the relationships among the insurable risk, background risk and ambiguity parameter. We obtain the deductible insurance is the optimal insurance while they meet specific dependence structures. 展开更多
关键词 Optimal Insurance Monotone Hazard Ratio Order Smooth ambiguity Model Background Risk belief Heterogeneity structure
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Basic principles of the whole petroleum system
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作者 JIA Chengzao PANG Xiongqi SONG Yan 《Petroleum Exploration and Development》 SCIE 2024年第4期780-794,共15页
This paper expounds the basic principles and structures of the whole petroleum system to reveal the pattern of conventional oil/gas-tight oil/gas-shale oil/gas sequential accumulation and the hydrocarbon accumulation ... This paper expounds the basic principles and structures of the whole petroleum system to reveal the pattern of conventional oil/gas-tight oil/gas-shale oil/gas sequential accumulation and the hydrocarbon accumulation models and mechanisms of the whole petroleum system.It delineates the geological model,flow model,and production mechanism of shale and tight reservoirs,and proposes future research orientations.The main structure of the whole petroleum system includes three fluid dynamic fields,three types of oil and gas reservoirs/resources,and two types of reservoir-forming processes.Conventional oil/gas,tight oil/gas,and shale oil/gas are orderly in generation time and spatial distribution,and sequentially rational in genetic mechanism,showing the pattern of sequential accumulation.The whole petroleum system involves two categories of hydrocarbon accumulation models:hydrocarbon accumulation in the detrital basin and hydrocarbon accumulation in the carbonate basin/formation.The accumulation of unconventional oil/gas is self-containment,which is microscopically driven by the intermolecular force(van der Waals force).The unconventional oil/gas production has proved that the geological model,flow model,and production mechanism of shale and tight reservoirs represent a new and complex field that needs further study.Shale oil/gas must be the most important resource replacement for oil and gas resources of China.Future research efforts include:(1)the characteristics of the whole petroleum system in carbonate basins and the source-reservoir coupling patterns in the evolution of composite basins;(2)flow mechanisms in migration,accumulation,and production of shale oil/gas and tight oil/gas;(3)geological characteristics and enrichment of deep and ultra-deep shale oil/gas,tight oil/gas and coalbed methane;(4)resource evaluation and new generation of basin simulation technology of the whole petroleum system;(5)research on earth system-earth organic rock and fossil fuel system-whole petroleum system. 展开更多
关键词 whole petroleum system theory structure of whole petroleum system sequential accumulation pattern hydrocarbon accumulation model of the whole petroleum system self-containment hydrocarbon accumulation mechanism geological model and flow model of shale and tight oil/gas
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From In-Out Duality to the Foundation of Social Quantum Mechanics
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作者 Kyoung-Il Ko 《Open Journal of Applied Sciences》 2024年第4期893-926,共34页
This paper introduces a framework of in-out duality, merging insights from quantum mechanics with social sciences to illuminate the complex interplay between internal potentialities and external manifestations. It art... This paper introduces a framework of in-out duality, merging insights from quantum mechanics with social sciences to illuminate the complex interplay between internal potentialities and external manifestations. It articulates foundational, mathematical axioms (Entanglement, Homogeneity, Emergence, and Measurement) that underpin the dynamics of systems, emphasizing the interconnectedness and emergent behaviors resulting from internal and external interactions. By exploring quantum concepts like coherence, entanglement, and superposition, the paper proposes an interdisciplinary approach termed Quantum Social Mechanics. This approach challenges classical paradigms, advocating for a reevaluation of conventional notions through the lens of quantum principles. The paper argues that understanding the universe’s complexities requires a synthesis of motion states and potential states, suggesting a paradigm shift towards integrating quantum mechanics into the philosophical foundation of social theory. Through this comprehensive framework, the paper aims to foster a deeper understanding of the universe’s interconnected nature and the dynamic processes that govern the emergence of complex systems and behaviors. 展开更多
关键词 ontology METa-theory Quantum Social Science structure DUaLITY ENTaNGLEMENT
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Investigation of the structural, electronic and mechanical properties of CaO–SiO_(2) compound particles in steel based on density functional theory 被引量:1
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作者 Chao Gu Ziyu Lyu +1 位作者 Qin Hu Yanping Bao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第4期744-755,共12页
CaO–SiO_(2)compounds compromise one of the most common series of oxide particles in liquid steels, which could significantly affect the service performance of the steels as crack initiation sites. However, the struct... CaO–SiO_(2)compounds compromise one of the most common series of oxide particles in liquid steels, which could significantly affect the service performance of the steels as crack initiation sites. However, the structural, electronic, and mechanical properties of the compounds in CaO–SiO_(2)system are still not fully clarified due to the difficulties in the experiments. In this study, a thorough investigation of these properties of CaO–SiO_(2)compound particles in steels was conducted based on first-principles density functional theory. Corresponding phases were determined by thermodynamic calculation, including gamma dicalcium silicate(γ-C2S), alpha-prime(L) dicalcium silicate(αL′-C2S), alpha-prime(H) dicalcium silicate(αH′-C2S), alpha dicalcium silicate(α-C2S), rankinite(C3S2), hatrurite(C3S), wollastonite(CS), and pseudowollastonite(Ps-CS). The results showed that the calculated crystal structures of the eight phases agree well with the experimental results. All the eight phases are stable according to the calculated formation energies, and γ-C2S is the most stable. O atom contributes the most to the reactivity of these phases. The Young’s modulus of the eight phases is in the range of 100.63–132.04 GPa. Poisson’s ratio is in the range of0.249–0.281. This study provided further understanding concerning the CaO–SiO_(2)compound particles in steels and fulfilled the corresponding property database, paving the way for inclusion engineering and design in terms of fracture-resistant steels. 展开更多
关键词 CaO–SiO_(2) density functional theory structural property electronic property mechanical property
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The action mechanisms and structures designs of F-containing functional materials for high performance oxygen electrocatalysis 被引量:1
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作者 Gang Wang Shuwei Jia +7 位作者 Hongjing Gao Yewen Shui Jie Fan Yixia Zhao Lei Li Weimin Kang Nanping Deng Bowen Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期377-397,I0010,共22页
Non-renewable fossil fuels have led to serious problems such as global warming,environmental pollution,etc.Oxygen electrocatalysis including oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)plays a cent... Non-renewable fossil fuels have led to serious problems such as global warming,environmental pollution,etc.Oxygen electrocatalysis including oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)plays a central role in clean energy conversion,enabling a number of sustainable processes for future air battery technologies.Fluorine,as the most electronegative element(4.0)not only can induce more efficient regulation for the electronic structure,but also can bring more abundant defects and other novel effects in materials selection and preparation for favorable catalysis with respect to the other nonmetal elements.However,an individual and comprehensive overview of fluorine-containing functional materials for oxygen electrocatalysis field is still blank.Therefore,it is very meaningful to review the recent progresses of fluorine-containing oxygen electrocatalysts.In this review,we first systematically summarize the controllable preparation methods and their possible development directions based on fluorine-containing materials from four preparation methods.Due to the strong electron-withdrawing properties of fluorine,its control of the electronic structure can effectively enhance the oxygen electrocatalytic activity of the materials.In addition,the catalytic enhancement effect of fluorine on carbonbased materials also includes the prevent oxidation and the layer peeling,and realizes the precise atomic control.And the catalytic improvement mechanism of fluorine containing metal-based compounds also includes the hydration of metal site,the crystal transformation,and the oxygen vacancy induction.Then,based on their various dimensions(0D–3D),we also have summarized the advantages of different morphologies on oxygen electrocatalytic performances.Finally,the prospects and possible future researching direction of F-containing oxygen electrocatalysts are presented(e.g.,novel pathways,advanced methods for measurement and simulation,field assistance and multi-functions).The review is considered valuable and helpful in exploring the novel designs and mechanism analyses of advanced fluorine-containing electrocatalysts. 展开更多
关键词 Fluorine-containing functional materials action mechanisms and structure designs Density functional theory Oxygen evolution reaction Oxygen reduction reaction
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Developments and Applications of Neutrosophic Theory in Civil Engineering Fields:A Review
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作者 Zhenhan Zhang Jun Ye 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期887-916,共30页
Neutrosophic theory can effectively and reasonably express indeterminate,inconsistent,and incomplete information.Since Smarandache proposed the neutrosophic theory in 1998,neutrosophic theory and related research have... Neutrosophic theory can effectively and reasonably express indeterminate,inconsistent,and incomplete information.Since Smarandache proposed the neutrosophic theory in 1998,neutrosophic theory and related research have been developed and applied to many important fields.Indeterminacy and fuzziness are one of the main research issues in the field of civil engineering.Therefore,the neutrosophic theory is very suitable for modeling and applications of civil engineering fields.This review paper mainly describes the recent developments and applications of neutrosophic theory in four important research areas of civil engineering:the neutrosophic decision-making theory and applied methods,the neutrosophic evaluation methods and applications of slope stability,the neutrosophic expressions and analyses of rock joint roughness coefficient,and the neutrosophic structural optimization methods and applications.In terms of these research achievements in the four areas of civil engineering,the neutrosophic theory demonstrates its advantages in dealing with the indeterminate and inconsistent issues in civil engineering and the effectiveness and practicability of existing applied methods.In the future work,the existing research results will be further improved and extended in civil engineering problems.In addition,the neutrosophic theory will also have better application prospects in other fields of civil engineering. 展开更多
关键词 Neutrosophic theory civil engineering DECISIon-MaKING slope stability joint roughness coefficient structural optimization
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Study on Construction of Forestry Socialized Service Systems Based on Barnard's Organizational Structure Theory
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作者 WANG Can-fu CHENG Xiao-qiu 《Agricultural Science & Technology》 CAS 2011年第4期603-607,共5页
Construction of forestry socialized service systems is the important content for reform of collective forestry tenure systems.Based on the necessity,possibility and problem of construction of forestry socialized servi... Construction of forestry socialized service systems is the important content for reform of collective forestry tenure systems.Based on the necessity,possibility and problem of construction of forestry socialized service system,according to Barnard's Organizational Structure theory,the path and countermeasure of forestry socialized service system in China are discussed. 展开更多
关键词 FORESTRY Construction of socialized service systems Modern organizational structure theory
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Coexistence Theory of Slag Structure and Its Application to Calculation of Oxidizing Capability of Slag Melts 被引量:29
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作者 ZHANG Jian 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2003年第1期1-10,共10页
The coexistence theory of slag structure and it's application to calculation of the oxidizing capabilities of slag melts is described. It is shown that the law of mass action can be widely applied to the calculati... The coexistence theory of slag structure and it's application to calculation of the oxidizing capabilities of slag melts is described. It is shown that the law of mass action can be widely applied to the calculation of oxidizing capabilities of slag melts in combination with the coexistence theory of slag structure.For slag melts containing basic oxides FeO and MnO, their oxidizing capabilities can be expressed by N Fe tO =N FeO +6N Fe 2O 3 , while for slag melts containing basic oxides CaO, MgO, etc., in addition to FeO and MnO, their oxidizing capabilities can be given as N Fe tO =N FeO +6N Fe 2O 3 +8N Fe 3O 4 . 展开更多
关键词 oxidizing capability coexistence theory slag structure aCTIVITY mass action concentration
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Mobility Analysis of the Deployable Structure of SLE Based on Screw Theory 被引量:14
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作者 SUN Yuantao WANG Sanmin +1 位作者 LI Jianfeng ZHI Changjian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第4期793-800,共8页
Scissor-like element has a number of applications in deployable structures such as planar deployable structure (PDS) and ring deployable structure(RDS). However, the mobility analysis of the multi-loop deployable stru... Scissor-like element has a number of applications in deployable structures such as planar deployable structure (PDS) and ring deployable structure(RDS). However, the mobility analysis of the multi-loop deployable structures is made more difficulty by the traditional mobility formula, because the deployable structure is a very complex structure with multi-loop. Therefore, On the basis of screw theory, the calculation method of mobility of deployable structures of SLE is thoroughly discussed. In order to investigate the mobility, decomposing and composing structures(DCS) are developed, and the basic units are able to be obtained. On the basis of the deployable structures’ geometrical characteristics, there exists a closed-loop quadrilateral structure and some non-closed-loop quadrilateral structures in PDS. Also, a six legs parallel structure is present in RDS. The basic units’ mobility can be solved by both the methods of screw theory and topology constraint graphs. Then, composing the related basic units, the formula of planar deployable structures’ mobility can be built and solves the mobility of ring deployable structure. The analysis method solves the mobility analysis of the multi-loop deployable structures which is difficulty by the traditional method, and plays an important role in further research about the mobility of other complex deployable structures. 展开更多
关键词 Scissor-like element(SLE) screw theory decomposing and composing structures (DCS) MOBILITY
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