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BASIC EQUATIONS, THEORY AND PRINCIPLE OF COMPUTATIONAL STOCK MARKET (Ⅰ)──BASIC EQUATIONS
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作者 云天铨 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第2期154-162,共9页
This paper studies computational stock market by using network model and similar methodology used in solid mechanics. Four simultaneous basic equations, i. e., equation of interest rate and amount of circulating fond... This paper studies computational stock market by using network model and similar methodology used in solid mechanics. Four simultaneous basic equations, i. e., equation of interest rate and amount of circulating fond, equations of purchasing and selling of share, equation of changing rate of share price, and equation of interest rate, share price and its changing rate, have been established. Discussions mainly on the solution and its simple applications of the equation of interest rate and amount of circulating fond are given. The discussions also involve the proof of tending to the equilibrium state of network of stock market based on the time discrete form of the equation by using Banach theorem of contraction mapping, and the influence of amount of circulating fond with exponential attenuation due to the decreasing of banking interest rate.Keyworks: stock market; network model; differential equation; contraction mapping; elasticity; methodology 展开更多
关键词 BASIC EQUATIONS FORT theory AND principle OF COMPUTATIONAL STOCK MARKET
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The Principle of Differentiation into Physical and Mathematical Theories
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作者 Anatoly Parfyonov 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1208-1216,共9页
The article formulates the main principle of physics, which underlies this science. This principle has been called by the author of this article the Principle of differentiation into physical and mathematical theories... The article formulates the main principle of physics, which underlies this science. This principle has been called by the author of this article the Principle of differentiation into physical and mathematical theories. The article gives examples of the application of this principle in quantum mechanics and cosmology. A more detailed proof of the principle of equivalence of the electromagnetic field and the field of strong interaction to a free material particle is given. This principle, formulated in the article “Electrodynamics in Curvilinear Coordinates and the Equation of a Geodesic Line”, revealed the nature of the mass of elementary particles and became the basis for the formulation of the Principle of differentiation into physical and mathematical theories. 展开更多
关键词 Origin of the Universe Expansion of the Universe Corpuscular-Wave Dualism The principle of Differentiation into Physical and Mathematical Theories
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Density Functional Theory for Battery Materials 被引量:10
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作者 Qiu He Bin Yu +1 位作者 Zhaohuai Li Yan Zhao 《Energy & Environmental Materials》 2019年第4期264-279,共16页
Batteries are the most widely used energy storage devices, and the lithiumion battery is the most heavily commercialized and most widely used battery type in the industry. However, the current rapid development of soc... Batteries are the most widely used energy storage devices, and the lithiumion battery is the most heavily commercialized and most widely used battery type in the industry. However, the current rapid development of society requires a major advancement in battery materials to achieve high capacity,long life cycle, low cost, and reliable safety. Therefore, many new efficient energy storage materials and battery systems are being developed and explored, and their working mechanisms must be clearly understood before industrial application. In recent years, density functional theory (DFT) has been employed in the energy storage field and has made significant contributions to the understanding of electrochemical reaction mechanisms and to virtual screening of promising energy storage materials. In this review,the applications of DFT to battery materials are summarized and exemplified by some representative and up-to-date studies in the literature. The main focuses in this review include the following:1) structural stability estimation by cohesive energy, formation energy, Gibbs free energy, and phonon dispersion spectra calculations;2) the Gibbs free energy calculations for electrochemical reactions, corresponding open-circuit voltage, and theoretical capacity predictions of batteries;3) the analyses of molecule orbitals, band structures, density of states (DOS), and charge distribution of battery materials;4) ion transport kinetics in battery materials;5) simulations of adsorption processes. We conclude the review with the discussion of the assessments and validation of the popular functionals against several benchmarks, and a few suggestions have been given for the selection of density functionals for battery material systems. 展开更多
关键词 BATTERY density functional theory first principle theory theoretical calculation
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Influence of nickel(II) oxide surface magnetism on molecule adsorption: A first-principles study
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作者 Chuan‐Qi Huang Wei‐Xue Li 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第10期1736-1748,共13页
The influence of the magnetism of transition metal oxide,nickel(II)oxide(NiO),on its surface reactivity and the dependence of surface reactivity on surface orientation and reactant magnetism were studied by density fu... The influence of the magnetism of transition metal oxide,nickel(II)oxide(NiO),on its surface reactivity and the dependence of surface reactivity on surface orientation and reactant magnetism were studied by density functional theory plus U calculations.We considered five different antiferromagnetically ordered structures and one ferromagnetically ordered structure,NiO(001)and Ni(011)surfaces,paramagnetic molecule NO,and nonparamagnetic molecule CO.The calculations showed that the dependence of surface energies on magnetism was modest,ranging from49to54meV/?2for NiO(001)and from162to172meV/?2for NiO(011).On NiO(001),both molecules preferred the top site of the Ni cation exclusively for all NiO magnetic structures considered,and calculated adsorption energies ranged from?0.33to?0.37eV for CO and from?0.42to?0.46eV for NO.On NiO(011),both molecules preferred the bridge site of two Ni cations irrespective of the NiO magnetism.It was found that rather than the long‐range magnetism of bulk NiO,the local magnetic order of two coordinated Ni cations binding to the adsorbed molecule had a pronounced influence on adsorption.The calculated NO adsorption energy at the(↑↓)bridge sites ranged from?0.99to?1.05eV,and become stronger at the(↑↑)bridge sites with values of?1.21to?1.30eV.For CO,although the calculated adsorption energies at the(↑↓)bridge sites(?0.73to?0.75eV)were very close to those at the(↑↑)bridge sites(?0.71to?0.72eV),their electron hybridizations were very different.The present work highlights the importance of the local magnetic order of transition metal oxides on molecular adsorption at multi‐fold sites. 展开更多
关键词 MAGNETISM Surface orientation Molecule adsorption First‐principles theory Electronic structure
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Theoretical calculations of structural, electronic, and elastic properties of CdSe_(1-x)Te_x:A first principles study
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作者 M Shakil Muhammad Zafar +3 位作者 Shabbir Ahmed Muhammad Raza-ur-rehman Hashmi M A Choudhary T Iqbal 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期324-330,共7页
The plane wave pseudo-potential method was used to investigate the structural, electronic, and elastic properties of Cd Se_(1-x)Te_x in the zinc blende phase. It is observed that the electronic properties are improv... The plane wave pseudo-potential method was used to investigate the structural, electronic, and elastic properties of Cd Se_(1-x)Te_x in the zinc blende phase. It is observed that the electronic properties are improved considerably by using LDA + U as compared to the LDA approach. The calculated lattice constants and bulk moduli are also comparable to the experimental results. The cohesive energies for pure Cd Se and Cd Te binary and their mixed alloys are calculated. The second-order elastic constants are also calculated by the Lagrangian theory of elasticity. The elastic properties show that the studied material has a ductile nature. 展开更多
关键词 first principles calculations density functional theory II–VI semiconductors structural electronic and elastic properties
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The patient suicide attempt-An ethical dilemma case study 被引量:1
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作者 Lin Jie 《International Journal of Nursing Sciences》 2015年第4期408-413,共6页
Case description:Nurses face more and more ethical dilemmas during their practice nowadays,especially when they are taking care of the patient at end of life stage.The case study demonstrates an ethical dilemma when n... Case description:Nurses face more and more ethical dilemmas during their practice nowadays,especially when they are taking care of the patient at end of life stage.The case study demonstrates an ethical dilemma when nursing staff are taking care of an end stage aggressive prostate cancer patient Mr Green who expressed the suicide thoughts to one of the nurses and ask that nurse keep secret for him in Brisbane,QLD,Australia.Ethical dilemma identification:The ethical dilemma is identified as“if the nursing staff should tell other health care team members about patient's suicide attempt without patient's consent”.Analysis:To better solving this case and making the best moral decision,the ethical theory,the ethical principles and the Australian nurses'code of ethics values statement,the associated literature relative with this case are analyzed before the decision making.Ethical decision making:After consider all of the above factors,in this case,the best ethical decision for the patient is that the nurse share the information of Mr Green's suicide attempt with other health care professionals.Results:In Mr Green's case,the nurse chose to share the information of Mr Green's suicide attempt with other health care professionals.The nursing team followed the self-harm and suicide protocol of the hospital strictly,they maintained the effective communication with Mr Green,identified the factors which cause patient's suicide attempt,provided the appropriate nursing intervention to deal will these risk factors and collaborated with other health care professionals to prefect the further care.The patient transferred to a palliative care service with no sign of suicide attempt and other self-harm behaviors and passed away peacefully 76 days after discharged with his relatives and pastors accompany. 展开更多
关键词 Ethical dilemmas Suicide attempt Ethical theory and principles
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Ab initio investigation of photoinduced non-thermal phase transition inβ-cristobalite
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作者 冯世全 臧华平 +2 位作者 王永强 程新路 岳金胜 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期723-728,共6页
Using the linear-response method, we investigate the phonon properties of β-cristobalite crystal under electronic ex- citation effect. We find that the transverse-acoustic phonon frequency becomes imaginary as the el... Using the linear-response method, we investigate the phonon properties of β-cristobalite crystal under electronic ex- citation effect. We find that the transverse-acoustic phonon frequency becomes imaginary as the electron temperature is increased, which means that the lattice of β-cristobalite becomes unstable under intense laser irradiation. In addition, for the optic phonon mode, the LO(H)-TO(H) splitting disappears when the electronic temperature reaches a certain value, corresponding to the whole transverse-acoustic phonon branches becoming negative. It means that the electronic excitation destroys the macroscopic electric field of β-cristobalite. Based on the calculated phonon band structures, some thermo- dynamic properties are calculated as a function of temperature at different electronic temperatures. These investigations provide evidence that non-thermal melting takes place during a femtosecond pulse laser interaction with β-cristobalite. 展开更多
关键词 first principles theory thermodynamic properties non-thermal melting electronic excitation
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Basic theories and development of Miao medicine
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作者 Minke Tang Linglong Luo +2 位作者 Chi Zhang Jiahui Wu Xueyong Wang 《Journal of Traditional Chinese Medical Sciences》 2021年第S01期22-26,共5页
Miao is an important ethnic minority in China.Miao medicine(MM)is a pivotal of traditional Chinese medicine.It is an accumulation of the Miao people's experience fighting against diseases for thousands of years an... Miao is an important ethnic minority in China.Miao medicine(MM)is a pivotal of traditional Chinese medicine.It is an accumulation of the Miao people's experience fighting against diseases for thousands of years and has been an important part of the Miao culture.The origin of MM is closely related to Miao culture,customs,and habits.MM gradually formed a traditional medical theoretical system with obvious regional characteristics,distinctive cultural characteristics,and unique efficacy.In this paper,we intro-duce and review the unique theoretical system of MM,including the basic theory of MM,the theory of medicine,nature,taste,and channel tropism,and the theory of entering the shelf.In addition,we summarize the development of MM to provide an overview of the theoretical characteristics and industrialisation of MM that is accessible to everyone. 展开更多
关键词 Miao medicine HISTORY Three elements theory of two principles Eight flavors
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Emergent perspective of gravity and dark energy
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作者 T.Padmanabhan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第8期891-916,共26页
There is sufficient amount of internal evidence in the nature of gravitational theories to indicate that gravity is an emergent phenomenon like, e.g, elasticity. Such an emergent nature is most apparent in the structu... There is sufficient amount of internal evidence in the nature of gravitational theories to indicate that gravity is an emergent phenomenon like, e.g, elasticity. Such an emergent nature is most apparent in the structure of gravitational dynamics. It is, however, possible to go beyond the field equations and study the space itseff as emer- gent in a well-defined manner in (and possibly only in) the context of cosmology. In the first part of this review, I describe various pieces of evidence which show that gravitational field equations are emergent. In the second part, I describe a novel way of studying cosmology in which I interpret the expansion of the universe as equivalent to the emergence of space itself. In such an approach, the dynamics evolves towards a state of holographic equipartition, characterized by an equality in the number of bulk and surface degrees of freedom in a region bounded by the Hubble radius. This prin- ciple correctly reproduces the standard evolution of a Friedmann universe. Further, (a) it demands the existence of an early inflationary phase as well as late time accelera- tion for its successful implementation and (b) allows us to link the value of late time cosmological constant to the e-folding factor during inflation. 展开更多
关键词 cosmology: theory -- cosmology: cosmological parameters -- emergentgravity -- holographic principle
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Investigation on AQ11, ID3 and the Principle of Discernibility Matrix 被引量:2
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作者 王珏 崔佳 赵凯 《Journal of Computer Science & Technology》 SCIE EI CSCD 2001年第1期1-12,共12页
The principle of discernibility matrix serves as a tool to discuss and analyze two algorithms of traditional inductive machine learning, AQ11 and ID3. The results are: (1) AQ11 and its family can be completely specifi... The principle of discernibility matrix serves as a tool to discuss and analyze two algorithms of traditional inductive machine learning, AQ11 and ID3. The results are: (1) AQ11 and its family can be completely specified by the principle of discernibility matrix; (2) ID3 can be partly, but not naturally, specified by the principle of discernibility matrix; and (3) The principle of discernibility matrix is employed to analyze Cendrowska sample set, and it shows the weaknesses of knowledge representation style of decision tree in theory. 展开更多
关键词 rough set theorys principle of discernibility matrix inductive ma- chine learning
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The electronic and magnetic properties of wurtzite Mn:CdS, Cr:CdS and Mn:Cr:CdS: first principles calculations 被引量:4
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作者 Azeem Nabi Zarmeena Akhtar +2 位作者 Tahir Iqbal Atif Ali Muhammad Arshad Javid 《Journal of Semiconductors》 EI CAS CSCD 2017年第7期36-43,共8页
In this article, density functional theory(DFT) based on generalized gradient approximation(GGA)and GGACU, U is Hubbard term, is used to study the electronic properties of CdS doped with different dopants(Cr, Mn... In this article, density functional theory(DFT) based on generalized gradient approximation(GGA)and GGACU, U is Hubbard term, is used to study the electronic properties of CdS doped with different dopants(Cr, Mn). The calculations are carried out for Mn-doped CdS, Cr-doped CdS, and co-doping of Mn/Cr in CdS simultaneously. It is found that hopping of electrons is possible with Cr:CdS and Mn:Cr:CdS while Mn:CdS does not allow the hopping of electrons. Moreover, double exchange interactions are observed in Cr:CdS and d-d superexchange interactions are observed in Mn:CdS. Now the problem becomes interesting when one magnetic ion(Cr) supporting double exchange interactions and another ion(Mn) supporting d-d super-exchange interactions are doped simultaneously in the same system(CdS). The co-doped CdS is more stable even at high Curie temperature due to p-d double exchange interactions and d-d super exchange interactions. Furthermore, the Cr-3d and Mn-3d states present in-between the band gap are responsible for inner shell transitions and hence for optical properties.Therefore, the co-doped system is taken into account to enhance its applications in the field of spintronic and magneto-optical devices. 展开更多
关键词 wurtzite first principles density functional theory
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Is There a Minimum Electrophilicity Principle in Chemical Reactions? 被引量:1
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作者 NOORIZADEH, Siamak 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2007年第10期1439-1444,共6页
For 25 simple reactions, the changes of the hardness (△η), polarizability (△α) and electrophilicity index (△ω) and their cube-roots (△η^1/3, △α^1/3, △ω^1/3) were calculated. It is shown that althou... For 25 simple reactions, the changes of the hardness (△η), polarizability (△α) and electrophilicity index (△ω) and their cube-roots (△η^1/3, △α^1/3, △ω^1/3) were calculated. It is shown that although the Maximum Hardness and Minimum Polarizability Principles are not valid for all reactions, but in most cases △ω^1/3〈0, whereas we always find △ω〈0. Our observation implies to this fact that for those chemical reactions in which the number of moles decreases or at least remains constant, the most stable species (reactants or products) have the lowest sum of electrophilicities. In other words "the natural direction of a chemical reaction is toward a state of minimum electrophilicity". This fact may be called Minimum Electrophilicity Principle (MEP). 展开更多
关键词 maximum hardness principle minimum polarizability principle minimum electrophilicity principle density functional theory
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