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The Dynamic System Theory of Legal Protection for Personal Information Rights Infringement
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作者 莫杨燊 NI Weis 《The Journal of Human Rights》 2024年第1期143-172,共30页
The advent of the big data era has presented unprecedented challenges to remedies for personal information infringement in areas such as damage assessment,proof of causation,determination of illegality,fault assessmen... The advent of the big data era has presented unprecedented challenges to remedies for personal information infringement in areas such as damage assessment,proof of causation,determination of illegality,fault assessment,and liability.Traditional tort law is unable to provide a robust response for these challenges,which severely hinders human rights protection in the digital society.The dynamic system theory represents a third path between fixed constitutive elements and general clauses.It both overcomes the rigidity of the“allor-nothing”legal effect evaluation mechanism of the“element-effect”model and avoids the uncertainty of the general clause model.It can effectively enhance the flexibility of the legal system in responding to social changes.In light of this,it is necessary to construct a dynamic foundational evaluation framework for personal information infringement under the guidance of the dynamic system theory.By relying on the dynamic interplay effect of various foundational evaluation elements,this framework can achieve a flexible evaluation of the constitutive elements of liability and the legal effects of liability for personal information infringement.Through this approach,the crisis of personal information infringement in the era of big data can be mitigated,and the realization of personal information rights as digital human rights can be promoted. 展开更多
关键词 personal information digital human rights dynamic system theory constitutive elements of torts LIABILITY
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Charge self-consistent dynamical mean field theory calculations incombination with linear combination of numerical atomic orbitalsframework based density functional theory
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作者 Xin Qu Peng Xu +6 位作者 Zhiyong Liu Jintao Wang Fei Wang Wei Huang Zhongxin Li Weichang Xu Xinguo Ren 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期62-69,共8页
We present a formalism of charge self-consistent dynamical mean field theory(DMFT)in combination with densityfunctional theory(DFT)within the linear combination of numerical atomic orbitals(LCNAO)framework.We implemen... We present a formalism of charge self-consistent dynamical mean field theory(DMFT)in combination with densityfunctional theory(DFT)within the linear combination of numerical atomic orbitals(LCNAO)framework.We implementedthe charge self-consistent DFT+DMFT formalism by interfacing a full-potential all-electron DFT code with threehybridization expansion-based continuous-time quantum Monte Carlo impurity solvers.The benchmarks on several 3d,4fand 5f strongly correlated electron systems validated our formalism and implementation.Furthermore,within the LCANOframework,our formalism is general and the code architecture is extensible,so it can work as a bridge merging differentLCNAO DFT packages and impurity solvers to do charge self-consistent DFT+DMFT calculations. 展开更多
关键词 dynamical mean field theory density functional theory strongly correlated electrons
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Suppression and synchronization of chaos in uncertain time-delay physical system
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作者 Israr Ahmad Muhammad Shafiq 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期416-437,共22页
The mechanical horizontal platform(MHP)system exhibits a rich chaotic behavior.The chaotic MHP system has applications in the earthquake and offshore industries.This article proposes a robust adaptive continuous contr... The mechanical horizontal platform(MHP)system exhibits a rich chaotic behavior.The chaotic MHP system has applications in the earthquake and offshore industries.This article proposes a robust adaptive continuous control(RACC)algorithm.It investigates the control and synchronization of chaos in the uncertain MHP system with time-delay in the presence of unknown state-dependent and time-dependent disturbances.The closed-loop system contains most of the nonlinear terms that enhance the complexity of the dynamical system;it improves the efficiency of the closed-loop.The proposed RACC approach(a)accomplishes faster convergence of the perturbed state variables(synchronization errors)to the desired steady-state,(b)eradicates the effect of unknown state-dependent and time-dependent disturbances,and(c)suppresses undesirable chattering in the feedback control inputs.This paper describes a detailed closed-loop stability analysis based on the Lyapunov-Krasovskii functional theory and Lyapunov stability technique.It provides parameter adaptation laws that confirm the convergence of the uncertain parameters to some constant values.The computer simulation results endorse the theoretical findings and provide a comparative performance. 展开更多
关键词 chaotic horizontal platform system chaos suppression chaos synchronization robust adaptive control Lyapunov stability theory
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Theoretical and numerical research on the dynamic launch response of carbon fiber composite cartridges
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作者 Ruijie Zhang Hui Xu +2 位作者 Chenlei Huang Kun Liu Zhilin Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期426-436,共11页
Understanding the dynamic response of composite material cartridges during the firing process is of great significance for improving their reliability and safety.A theoretical model describing the dynamic response of ... Understanding the dynamic response of composite material cartridges during the firing process is of great significance for improving their reliability and safety.A theoretical model describing the dynamic response of composite material cartridges is established based on the thick-walled cylinder theory and rate-dependent constitutive model of composite materials.The correctness of the theoretical model is validated through finite element simulations of cartridge deformation.The influence of chamber pressure and cartridge wall thickness on the cartridge's deformation process and stress distribution is analyzed.The results indicate that the primary deformation of composite material cartridges inside the chamber is elastic deformation.Compared to metal cartridges,composite material cartridges require higher pressure for touching-chamber and are more prone to developing gaps after unloading to ensure smooth extraction.During the deformation process,the touching-chamber behavior of the cartridge can improve the stress distribution.Under the same chamber pressure,the touching-chamber behavior can reduce the circumferential stress by approximately 30%.The inner wall surface of the cartridge is a critical area that requires attention.The touching-chamber behavior can be facilitated by appropriately reducing the cartridge wall thickness while ensuring overall strength.This study can provide guidance for the optimization design of composite material cartridges. 展开更多
关键词 Composite material cartridges dynamic response Thick-walled cylinder theory Finite element simulation Toughing-chamber behavior
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Arrhythmia Detection by Using Chaos Theory with Machine Learning Algorithms
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作者 Maie Aboghazalah Passent El-kafrawy +3 位作者 Abdelmoty M.Ahmed Rasha Elnemr Belgacem Bouallegue Ayman El-sayed 《Computers, Materials & Continua》 SCIE EI 2024年第6期3855-3875,共21页
Heart monitoring improves life quality.Electrocardiograms(ECGs or EKGs)detect heart irregularities.Machine learning algorithms can create a few ECG diagnosis processing methods.The first method uses raw ECG and time-s... Heart monitoring improves life quality.Electrocardiograms(ECGs or EKGs)detect heart irregularities.Machine learning algorithms can create a few ECG diagnosis processing methods.The first method uses raw ECG and time-series data.The second method classifies the ECG by patient experience.The third technique translates ECG impulses into Q waves,R waves and S waves(QRS)features using richer information.Because ECG signals vary naturally between humans and activities,we will combine the three feature selection methods to improve classification accuracy and diagnosis.Classifications using all three approaches have not been examined till now.Several researchers found that Machine Learning(ML)techniques can improve ECG classification.This study will compare popular machine learning techniques to evaluate ECG features.Four algorithms—Support Vector Machine(SVM),Decision Tree,Naive Bayes,and Neural Network—compare categorization results.SVM plus prior knowledge has the highest accuracy(99%)of the four ML methods.QRS characteristics failed to identify signals without chaos theory.With 99.8%classification accuracy,the Decision Tree technique outperformed all previous experiments. 展开更多
关键词 ECG extraction ECG leads time series prior knowledge and arrhythmia chaos theory QRS complex analysis machine learning ECG classification
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Time/Space and Inertial System Reconsidered Based on the Adaptive Dynamical View
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作者 Tadashi Ando Ichiro Yamato 《Journal of Modern Physics》 2024年第11期1621-1631,共11页
We have succeeded in 2-slit interference simulation by assuming that a travelling particle interacts with its environment, getting information on the environmental condition according to the adaptive dynamics by Ohya,... We have succeeded in 2-slit interference simulation by assuming that a travelling particle interacts with its environment, getting information on the environmental condition according to the adaptive dynamics by Ohya, thus proposed the possibility that the entanglement comes from the interaction with the environment (Ando et al., 2023). This concept means that there should be no isolated or inertial system other than our unique universe space. Taking this message into account and assuming that the signal velocity is constant against our unique universe space, we reconsidered the inertial system and relativity theory by Galilei and Einstein and found several misunderstandings and errors. Time delay and Lorentz shrinkage were derived similarly to the prediction by special relativity theory, but Lorentz transformation and 4-dimensional time/space view were not. They must have implicitly and unconsciously assumed that any signals transfer information without giving any influences to any systems different from our adaptive dynamical view. We propose that their relativity theories should be reinterpreted in view of adaptive dynamics. 展开更多
关键词 Relativity theory Inertial system Adaptive dynamics INTERCONNECTION
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Constructing a Teaching Evaluation Model for the Course of Beijing World Cultural Heritage Based on Dynamic Assessment Theory
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作者 TAN Hao XIANYU Jing 《Sino-US English Teaching》 2023年第4期137-142,共6页
The rapid development of international tourism has led to an increasing demand for English professionals. In order to meet this demand, universities have placed greater emphasis on the quality and level of teaching in... The rapid development of international tourism has led to an increasing demand for English professionals. In order to meet this demand, universities have placed greater emphasis on the quality and level of teaching in the courses of tourism English. This paper proposes a dynamic evaluation model for tourism English courses, based on the principles of dynamic assessment theory, such as process-orientation, evaluation-teaching integration, and multiple interactions. Taking the course of Beijing World Cultural Heritage as an example, the model is instantiated to demonstrate the feasibility of applying dynamic assessment theory to tourism English courses and this model helps to provide a reference for the evaluation methods of English courses. 展开更多
关键词 dynamic assessment theory assessment mode Beijing World Heritage Course
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Poisson theory and integration method for a dynamical system of relative motion 被引量:3
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作者 张毅 尚玫 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期321-325,共5页
This paper focuses on studying the Poisson theory and the integration method of dynamics of relative motion. Equations of a dynamical system of relative motion in phase space are given. Poisson theory of the system is... This paper focuses on studying the Poisson theory and the integration method of dynamics of relative motion. Equations of a dynamical system of relative motion in phase space are given. Poisson theory of the system is established. The Jacobi last multiplier of the system is defined, and the relation between the Jacobi last multiplier and the first integrals of the system is studied. Our research shows that for a dynamical system of relative motion, whose configuration is determined by n generalized coordinates, the solution of the system can be found by using the Jacobi last multiplier if (2n-1) first integrals of the system are known. At the end of the paper, an example is given to illustrate the application of the results. 展开更多
关键词 dynamics of relative motion Poisson theory method of integration Jacobi last multiplier
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Characterization of the Atmospheric Dynamics in Riobamba City Using the Chaos Theory 被引量:1
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作者 Arquímides Haro Cecilia Limaico Yolanda Llosas 《Atmospheric and Climate Sciences》 2015年第4期441-449,共9页
Chaos studies all that is messy, disorganized and incoherent;mathematically the chaos is a dynamic system governed by nonlinear differential equations. Chaos has an unpredictable behavior;its dynamical is very sensiti... Chaos studies all that is messy, disorganized and incoherent;mathematically the chaos is a dynamic system governed by nonlinear differential equations. Chaos has an unpredictable behavior;its dynamical is very sensitive to the initial conditions. Atypical chaotic system is the atmosphere;this limits the knowledge about its behavior;but with the advance in the computers, the results that are obtained with the chaos theory improved significantly;the description of atmosphera and its results have extended to other fields of the science, as the economy, health and others. The object of this work was to determine the atmospheric dynamics in the Riobamba city using the theory of chaos, with meteorological data of the meteorological station of the ESPOCH of one year (2010) of data that were processed with model TISEAN. The results determine a hyperchaotic system, according to the coefficients of Lyapunov. 展开更多
关键词 chaos theory ATMOSPHERIC VARIABLES COEFFICIENTS of LYAPUNOV dynamics ENTROPY
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THE COUPLING DYNAMICAL MODELING THEORY OF FLEXIBLE MULTIBODY SYSTEM
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作者 Jiang, LZ Hong, JZ 《Acta Mechanica Solida Sinica》 SCIE EI 1999年第4期365-372,共8页
Based on the deformation theory of elastic beams, the coupling effect between the coupling displacements of a point on the middle line of beam and large overall motion is presented. The 'coupling matrix library... Based on the deformation theory of elastic beams, the coupling effect between the coupling displacements of a point on the middle line of beam and large overall motion is presented. The 'coupling matrix library' and Jourdain's variation principle and single direction recursive formulation method are used to establish the general coupling dynamical equations of flexible multibody system. Two typical examples show the coupling effect between coupling displacements and large overall motion on the dynamics of flexible multibody system consisting of beams. 展开更多
关键词 coupling displacement coupling dynamical modeling theory large overall motion single direction recursive formulation flexible multibody system
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Dynamical Systems Theory Compared to Game Theory: The Case of the Salamis’s Battle
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作者 Konstantina Founta Loukas Zachilas 《Applied Mathematics》 2021年第10期882-899,共18页
In this paper, we present an innovative non–linear, discrete, dynamical system trying to model the historic battle of Salamis between Greeks and Persians. September 2020 marks the anniversary of the 2500 years that h... In this paper, we present an innovative non–linear, discrete, dynamical system trying to model the historic battle of Salamis between Greeks and Persians. September 2020 marks the anniversary of the 2500 years that have passed since this famous naval battle which took place in late September 480 B.C. The suggested model describes very well the most effective strategic behavior between two participants during a battle (or in a war). Moreover, we compare the results of the Dynamical Systems analysis to Game Theory, considering this conflict as a “war game”. 展开更多
关键词 Discrete dynamical systems Modeling Strategic Behavior Game theory Battle of Salamis
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Developmental Routines of Oral English Ability for English Major Students:Based on Complex and Dynamic Systems Theory
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作者 MA Yi-ze CHEN Zheng 《Journal of Literature and Art Studies》 2022年第9期916-924,共9页
This study employs a Q methodology to explore the developmental routines of oral English ability for 12 English major students in China inspired by Complex and Dynamic Systems Theory(CDST).The data analysis suggests t... This study employs a Q methodology to explore the developmental routines of oral English ability for 12 English major students in China inspired by Complex and Dynamic Systems Theory(CDST).The data analysis suggests the next findings:(1)two developmental patterns emerge as the gradual improvement and the strong phase shift influenced by internal and external factors for interactions among different subsystems;(2)guided by CDST,the study proves the importance of self-organization and initial condition in previous studies.According to the above findings,It is highly suggested for teachers to form a holistic view of students’oral English development concerning the non-linear characteristic and individual differences. 展开更多
关键词 oral English Complex and dynamic systems theory(CDST) developmental routines Q methodology
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Evaluation of the Validity of Chaos Theory Based on Systems Thinking for Non-Physicists
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作者 Deok-Soo Cha Kyoung-Il Kim 《Open Journal of Applied Sciences》 2022年第5期845-854,共10页
Chaos theory was born in the 18th century, physicists still solve the nonlinear dynamic systematic problems within closed-loop systems such as ecosystems, three-body problems involving complexity, and others. Moreover... Chaos theory was born in the 18th century, physicists still solve the nonlinear dynamic systematic problems within closed-loop systems such as ecosystems, three-body problems involving complexity, and others. Moreover, it has been resolved these problems based on logical thinking using logical solutions with algebra and statistics such as chaos theory. The reason is determinism. Nevertheless, other scientists do not welcome the old chaos theory because the chaos theory is very imperfect and vague. Amazingly, in 2021, there is emerged, and an advanced and systematic solution based on system thinking;it was resolved by a non-physicist on behalf of physicists through interdisciplinary science and it is more perfect than the old chaos theory. Therefore, it is similar to the New World discovered by Columbus. This paper will prove that the existing chaos theory is invalid as a new solution emerges. Nevertheless, current physicists avoid approaching this study as much as possible. Therefore, other scientists have no reason to follow their invalid chaos theory unless physicists prove the validity of chaos theory. 展开更多
关键词 Nonlinear dynamics Control theory MATLAB systems Thinking
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Argа-Bilig theory in traditional Mongolian medicine:a theoretical and practical perspective 被引量:1
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作者 Tegele Si Xue-Mei Bao +2 位作者 Ming-Hai Fu Xiu-Mei Wang Laxinamujila Bai 《History & Philosophy of Medicine》 2024年第3期23-28,共6页
The concept of Arga and Bilig serves as a foundational principle in both ancient Mongolian philosophy and traditional Mongolian medicine (TMM). Arga, symbolized by brightness and associated with qualities of fire and ... The concept of Arga and Bilig serves as a foundational principle in both ancient Mongolian philosophy and traditional Mongolian medicine (TMM). Arga, symbolized by brightness and associated with qualities of fire and activity, complements Bilig, symbolized by darkness and representing attributes of water and stillness. Together, these opposing forces permeate all aspects of existence, from the genesis of parenthood to the interplay of day and night. Understanding Arga-Bilig is crucial for diagnosing and treating diseases, as it illuminates the source of imbalance within the body. This review provides an overview of the significance of Arga-Bilig in Mongolian philosophy and its application in TMM, emphasizing the dynamic interplay of these opposing forces and their role in maintaining balance and harmony within the body. 展开更多
关键词 traditional Mongolian medicine Arga and Bilig theory HOLISTIC dynamic interplay
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Half-metallic ferromagneticWeyl fermions related to dynamic correlations in the zinc-blende compound VAs
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作者 Xianyong Ding Haoran Wei +3 位作者 Ruixiang Zhu Xiaoliang Xiao Xiaozhi Wu Rui Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期528-533,共6页
The realization of 100%polarized topologicalWeyl fermions in half-metallic ferromagnets is of particular importance for fundamental research and spintronic applications.Here,we theoretically investigate the electronic... The realization of 100%polarized topologicalWeyl fermions in half-metallic ferromagnets is of particular importance for fundamental research and spintronic applications.Here,we theoretically investigate the electronic and topological properties of the zinc-blende compound VAs,which was deemed as a half-metallic ferromagnet related to dynamic correlations.Based on the combination of density functional theory and dynamical mean field theory,we uncover that the half-metallic ferromagnet VAs exhibits attractive Weyl semimetallic behaviors which are very close to the Fermi level in the DFT+U regime with effect U values ranging from 1.5 eV to 2.5 eV.Meanwhile,we also investigate the magnetization-dependent topological properties;the results show that the change of magnetization directions only slightly affects the positions of Weyl points,which is attributed to the weak spin–orbital coupling effects.The topological surface states of VAs projected on semi-infinite(001)and(111)surfaces are investigated.The Fermi arcs of all Weyl points are clearly visible on the projected Fermi surfaces.Our findings suggest that VAs is a fully spin-polarized Weyl semimetal with many-body correlated effects in the effective U values range from 1.5 eV to 2.5 eV. 展开更多
关键词 density functional theory Weyl semimetal dynamical mean field theory half metallic ferromagnet
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A stepwise approach to enhancing flotation of low-grade zinnwaldite through the cationic/DL-2-octanol/anionic reagent combinations: Behavior and mechanism analysis
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作者 Zhonghua Xue Yali Feng +2 位作者 Haoran Li Jinrong Ju Xingquan Du 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第6期881-891,共11页
In order to alleviate the pressure on the supply of lithium resources, this research proposes the use of binary/ternary collectors with high selectivity and collecting ability to enhance the flotation purification of ... In order to alleviate the pressure on the supply of lithium resources, this research proposes the use of binary/ternary collectors with high selectivity and collecting ability to enhance the flotation purification of low-grade zinnwaldite ore. The binary collector is a mixture of dodecylamine polyoxyethylene ether and DL-2-octanol. A binary collector is added first, followed by sodium oleate, known as a ternary collector. Under acidic conditions, the recovery of Li2O in the concentrate was increased by 8.26% with the binary collector and 13.70% with the ternary collector, compared to the dodecylamine polyoxyethylene ether. The binary collector enhanced the dispersibility of the single collector, while co-adsorption strengthened the hydrophobic nature of the zinnwaldite surface. Consequently, zinnwaldite particles,after the application of binary collector, displayed inter-particle flocculation and attachment to bubbles within 60×10^(-9)m compared to other particles. Ternary collector exhibited the capacity to lower critical micelle concentration and surface tension, subsequently inducing a denser and thicker hydrophobic layer through electrostatic forces, hydrophobic interactions, and chemical reactions. The objective of this research is to facilitate the recovery of lithium resources from low-grade ores in order to meet the needs of sustainable development. 展开更多
关键词 Zinnwaldite Molecular dynamics simulation FLOTATION Ternary collector Extended DLVO theory
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NMR-based analysis of the effect of moisture migration on sandstone pore structure under alternating wetting and drying conditions
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作者 Huasu Wang Jing Bi +2 位作者 Yu Zhao Chaolin Wang Jiabao Ma 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第8期1135-1150,共16页
The wetting-drying(W-D)cycle is a type of water–rock interaction.The pore structure of rock,such as shape,size,distribution and pore throat,affects fluid storage and transport.Fractal theory and experimental research... The wetting-drying(W-D)cycle is a type of water–rock interaction.The pore structure of rock,such as shape,size,distribution and pore throat,affects fluid storage and transport.Fractal theory and experimental research on the evolution characteristics of pore damage during the wet-dry erosion process are highly important for determining W-D damage.The mass and velocity of liquid migration are related to the pore size,porosity,fluid properties,etc.Experimental data show that the water absorption quality and velocity in rocks decrease with the number of wet-dry cycles.At the same test time,the mass and velocity of the SI water absorption method are smaller than those of the FI method.Under these two conditions,the amount and rate of water absorption represent the degree of water–rock interaction.Considering the pore evolution during the wet-dry cycling,an equation describing the motion of liquid in porous media was derived based on the imbibition-type separation model.The experimental data are in excellent agreement with the calculated values of the model.Permeability characteristics can affect the area and degree of rock deterioration as well as the development rate of pores and microcracks.Based on the interaction between permeability and pores,quantitative analysis of the weakening process(local damage)of rocks under W-D cycles can provide good reference indicators for evaluating the stability of geotechnical engineering. 展开更多
关键词 W-D cycle Capillary absorption Pore characteristic Fractal theory dynamic damage model
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Dynamic in situ reconstruction of NiSe_(2) promoted by interfacial Ce_(2)(CO_(3))_(2)O for enhanced water oxidation
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作者 Fengli Wei Jinghao Shen +6 位作者 Jiayin Xie Zuyang Luo Luyan Shi Tayirjan Taylor Isimjan Xiulin Yang Jieshan Qiu Bin Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期472-480,共9页
Understanding and manipulating the structural evolution of water oxidation electrocatalysts lays the foundation to finetune their catalytic activity.Herein,we present a synthesis of NiSe_(2)-Ce_(2)(CO_(3))_(2)O hetero... Understanding and manipulating the structural evolution of water oxidation electrocatalysts lays the foundation to finetune their catalytic activity.Herein,we present a synthesis of NiSe_(2)-Ce_(2)(CO_(3))_(2)O heterostructure and demonstrate the efficacy of interfacial Ce_(2)(CO_(3))2O in promoting the formation of catalytically active centers to improve oxygen evolution activity.In-situ Raman spectroscopy shows that incorporation of Ce_(2)(CO_(3))2O into NiSe_(2) causes a cathodic shift of the Ni^(2+)→Ni~(3+) transition potential.Operando electrochemical impedance spectroscopy reveals that strong electronic coupling at heterogeneous interface accelerates charge transfer process.Furthermore,density functional theory calculations suggest that actual catalytic active species of NiOOH transformed from NiSe_(2),which is coupled with Ce_(2)(CO_(3))_(2)O,can optimize electronic structure and decrease the free energy barriers toward fast oxygen evolution reaction(OER) kinetics.Consequently,the resultant NiSe_(2)-Ce_(2)(CO_(3))_(2)O electrode exhibits remarkable electrocatalytic performance with low overpotentials(268/304 mV@50/100 mA cm^(-2)) and excellent stability(50 mA cm^(-2) for 120 h) in the alkaline electrolyte.This work emphasizes the significance of modulating the dynamic changes in developing efficient electrocatalyst. 展开更多
关键词 dynamic reconstruction Oxygen evolution reaction HETEROSTRUCTURE In situ characterization Density functional theory
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Comparative study of nudged elastic band and molecular dynamics methods for diffusion kinetics in solid-state electrolytes
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作者 林啊鸣 石晶 +1 位作者 魏苏淮 孙宜阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期96-100,共5页
Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynam... Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynamics(MD)methods,provide powerful tools for the design of solid-state electrolytes.The MD method is usually the choice for studying the materials involving complex multiple diffusion paths or having disordered structures.However,it relies on simulations at temperatures much higher than working temperature.This paper studies the reliability of the MD method using the system of Na diffusion in MgO as a benchmark.We carefully study the convergence behavior of the MD method and demonstrate that total effective simulation time of 12 ns can converge the calculated diffusion barrier to about 0.01 eV.The calculated diffusion barrier is 0.31 eV from both methods.The diffusion coefficients at room temperature are 4.3×10^(-9) cm^(2)⋅s^(−1) and 2.2×10^(-9) cm^(2)⋅s^(−1),respectively,from the NEB and MD methods.Our results justify the reliability of the MD method,even though high temperature simulations have to be employed to overcome the limitation on simulation time. 展开更多
关键词 nudged elastic band method molecular dynamics solid electrolyte ion transport density func-tional theory
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A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well
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作者 Ji-Lin Fan Feng Zhang +3 位作者 Qian Chen Hao-Chen Song Lu-Yu Zhong Yue-Xiang Dai 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期244-251,共8页
Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and gas.However,the presence of inhomogeneous cement distribution a... Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and gas.However,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal density.In this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection system.The spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response functions.Combined with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal density.This approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal density.This accuracy level is ten times higher compared to density accuracy calculated using calibration equations.Overall,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry. 展开更多
关键词 Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration
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