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The Strange Relationship between the Momentum of a Photon Emitted from an Electron and the Momentum Acquired by the Electron
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作者 Koshun Suto 《Journal of Applied Mathematics and Physics》 2024年第7期2652-2664,共13页
In quantum mechanics, the energy of a hydrogen atom is minimized when the principal quantum number n is 1. However, the author has previously pointed out that the hydrogen atom has a state where n=0. An electron in th... In quantum mechanics, the energy of a hydrogen atom is minimized when the principal quantum number n is 1. However, the author has previously pointed out that the hydrogen atom has a state where n=0. An electron in the state where n=0has zero rest mass energy. However, a hydrogen atom has an energy level even lower than the n=0state. This is hard to accept from the standpoint of common sense. Thus, the author has previously pointed out that an electron at the energy level where n=0has zero energy because the positive energy mec2and negative energy −mec2cancel each other out. This paper elucidates the strange relationship between the momentum of a photon emitted when a hydrogen atom is formed by an electron with such characteristics, and the momentum acquired by the electron. 展开更多
关键词 Einstein’s energy-Momentum relationship energy-Momentum relationship in a Hydrogen Atom Momentum of a Photon Momentum of a Electron Negative energy Specific to the Electron Dark Matter
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Correlation of work function and stacking fault energy through Kelvin probe force microscopy and nanohardness in diluteα-magnesium
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作者 Yigit Türe Ali Arslan Kaya +2 位作者 Hüseyin Aydin Jiang Peng Servet Turan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期237-250,共14页
Electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-Ba systems.This investigation incorporated the difference in the‘Work ... Electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-Ba systems.This investigation incorporated the difference in the‘Work Function'(ΔWF)measured via Kelvin Probe Force Microscopy(KPFM),as a property directly affected by interatomic bond types,i.e.the electronic structure,nanoindentation measurements,and Stacking Fault Energy values reported in the literature.It was shown that the nano-hardness of the solid-solutionα-Mg phase changed in the order of Mg-Ca>Mg-Sr>Mg-Ba.Thus,it was shown,by also considering the nano-hardness levels,that SFE of a solid-solution is closely correlated with its‘Work Function'level.Nano-hardness measurements on the eutectics andΔWF difference between eutectic phases enabled an assessment of the relative bond strength and the pertinent electronic structures of the eutectics in the three alloys.Correlation withΔWF and at least qualitative verification of those computed SFE values with some experimental measurement techniques were considered important as those computational methods are based on zero Kelvin degree,relatively simple atomic models and a number of assumptions.As asserted by this investigation,if the results of measurement techniques can be qualitatively correlated with those of the computational methods,it can be possible to evaluate the electronic structures in alloys,starting from binary systems,going to ternary and then multi-elemental systems.Our investigation has shown that such a qualitative correlation is possible.After all,the SFE values are not treated as absolute values but rather become essential in comparative investigations when assessing the influences of alloying elements at a fundamental level,that is,free electron density distributions.Our study indicated that the principles of‘electronic metallurgy'in developing multi-elemental alloy systems can be followed via practical experimental methods,i.e.ΔWF measurements using KPFM and nanoindentation. 展开更多
关键词 Mg alloys Dilute alloys Work function Stacking fault energy Kelvin probe force microscopy Short range order Miedema NANOINDENTATION EUTECTICS
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An Analysis of Specific Categories of Birth Defects and Developmental Disabilities for Children of Participants of the Air Force Health Study
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作者 George J. Knafl 《Open Journal of Epidemiology》 2024年第2期312-330,共19页
Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. An... Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. Analyses were conducted of occurrence of 16 specific categories of birth defects and developmental disabilities. Children were categorized as conceived before and after the start of participants’ Vietnam War service. Children conceived before the start of Vietnam War service were treated as being conceived when their fathers had unquantifiable dioxin values. Children conceived after the start of Vietnam War service for participants with missing dioxin values were excluded from primary analyses, but were used to assess the impact of their exclusion on conclusions. Correlation between values for specific categories for multiple children fathered by the same participant was accounted for. The dose-response relationship was treated as a step function increasing for dioxin values larger than adaptively identified individual thresholds changing with the specific category. Results: For 15 of 16 specific categories, the probability of occurrence increased substantially for a sufficiently high dioxin level above identified thresholds. Exclusion of children due to missing dioxin likely did not affect these results. Conclusions: Results supported the conclusion of substantial adverse effects on a wide variety of specific categories of birth defects and developmental disabilities due to sufficiently high exposures to dioxin, a toxic contaminant of Agent Orange used for herbicide spraying in the Vietnam War. Results may hold more generally, but might also have been affected by a variety of limitations. 展开更多
关键词 Agent Orange Air force Health Study Birth Defects Developmental Disabilities DIOXIN Dose-Response relationship Vietnam War
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The relationship between energy consumption and economic growth and the development strategy of a low-carbon economy in Kazakhstan 被引量:7
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作者 XIONG Chuanhe YANG Degang +1 位作者 HUO Jinwei ZHAO Yannan 《Journal of Arid Land》 SCIE CSCD 2015年第5期706-715,共10页
Fossil energy is the material basis of human survival, economic development and social progress. The relationship between energy consumption and economic growth is becoming increasingly close. However, energy consumpt... Fossil energy is the material basis of human survival, economic development and social progress. The relationship between energy consumption and economic growth is becoming increasingly close. However, energy consumption is the major source of greenhouse gases, which can significantly affect the balance of the global ecosystem. It has become the common goal of countries worldwide to address climate change, reduce carbon dioxide emissions, and implement sustainable development strategies. In this study, we applied an approximate relationship analysis, a decoupling relationship analysis, and a trend analysis to explore the relationship between energy consumption and economic growth using data from Kazakhstan for the period of 1993-2010. The results demonstrated: (1) the total energy consumption and GDP in Kazakhstan showed a "U"-type curve from 1993 to 2010. This curve was observed because 1993-1999 was a period during which Kazakhstan transitioned from a republic to an independent country and experienced a difficult transition from a planned to a market economy. Then, the economic system became more stable and the industrial production increased rapidly because of the effective financial, monetary and industrial policy support from 2000 to 2010. (2) The relationships between energy con- sumption and carbon emissions, economic growth and energy exports were linked; the carbon emissions were mainly derived from energy consumption, and the dependence of economic growth on energy exports gradually increased from 1993 to 2010. Before 2000, the relationship between energy consumption and economic growth was in a recessional decoupling state because of the economic recession. After 2000, this relationship was in strong and weak decoupling states because the international crude oil prices rose and energy exports increased greatly year by year. (3) It is forecasted that Kazakhstan cannot achieve its goal of energy consumption by 2020. Therefore, a low-carbon economy is the best strategic choice to address climate change from a global perspective in Kazakhstan. Thus, we proposed strategies including the improvement of the energy consumption structure, the development of new energy and renewable energy, the use of cleaner production technologies, the adjustment and optimization of the industrial structure, and the expansion of forest areas. 展开更多
关键词 energy consumption economic growth the decoupling relationship analysis low-carbon economy Kazakhstan
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Gravitational Forces Explained as the Result of Anisotropic Energy Exchange between Baryonic Matter and Quantum Vacuum
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作者 Stefan L. Hahn 《Journal of Modern Physics》 2015年第8期1135-1148,共14页
Gravitational forces are explained as a result of energy exchange between baryonic matter having the property of mass and the Quantum Vacuum. The derivations are starting with a hypothesis that baryonic matter, partic... Gravitational forces are explained as a result of energy exchange between baryonic matter having the property of mass and the Quantum Vacuum. The derivations are starting with a hypothesis that baryonic matter, particles, atoms and molecules exchange energy with the Quantum Vacuum with zero balance. It is assumed that in absence of an external gravitation field the emission pattern is isotropic. There is no recoil force of radiation. The application of an external gravitation field induces an anisotropy which results in a recoil force of radiation. An ellipsoidal radiation pattern is applied. The eccentricity of the ellipsoid is defined using the maximum possible value of any gravitation field estimated to have the value about 5 × 1012 [m/s2]. A formula is derived for calculating the power of the isotropic radiation. It was shown that two masses attract due to the fact that gravitation field lowers the energy density of the Quantum Vacuum. Using the results of measurements of a binary neutron star by Taylor and Hulse (Nobel Prize in Physics 1993) it was shown that possibly gravitational waves carry negative energy. 展开更多
关键词 GRAVITATION Quantum Vacuum Negative energy RECOIL forceS
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THE RELATIONSHIPS BETWEEN THE POLARIZING FORCE OF CATIONS AND THE ELECTROPHILIC CHARACTER AND CATALYTIC PERFORMANCES OF PROMOTED Pt-Al_2O_3 CATALYST
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作者 Jia LIU Xi Yao YANG Li PANG Department of Chemistry,Peking University,Beijing,100871 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第3期261-262,共2页
The electronic modification effect of various metal oxides over Pt-Al;O;catalyst andthe relationships between the polarizing force of cations(PFC)and the electrophiliccharacter(EC)and catalytic performances(CP)o... The electronic modification effect of various metal oxides over Pt-Al;O;catalyst andthe relationships between the polarizing force of cations(PFC)and the electrophiliccharacter(EC)and catalytic performances(CP)of promoted Pt catalyst have been studiecby competitive hydrogenation reaction method(CHRM)and test reaction,i.e.hydrogena-tion of benzene and hydrogenolysis of cyclopentane. 展开更多
关键词 Pt EC the relationshipS between the POLARIZING force OF CATIONS and the ELECTROPHILIC CHARACTER and CATALYTIC PERFORMANCES OF PROMOTED Pt-Al2O3 CATALYST Al
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Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory
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作者 Yang Su Ze-Yu Li +3 位作者 Li-Le Liu Guo-Xiang Dong Xiao-Bao Wang Yong-Jing Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期198-207,共10页
Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pair... Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data. 展开更多
关键词 Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution
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Performances of a Stinger PDC cutter breaking granite: Cutting force and mechanical specific energy in single cutter tests 被引量:1
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作者 Chao Xiong Zhong-Wei Huang +4 位作者 Huai-Zhong Shi Rui-Yue Yang Gang Wu Han Chen Wen-Hao He 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1087-1103,共17页
The Stinger PDC cutter has high rock-breaking efficiency and excellent impact and wear resistance, which can significantly increase the rate of penetration (ROP) and extend PDC bit life for drilling hard and abrasive ... The Stinger PDC cutter has high rock-breaking efficiency and excellent impact and wear resistance, which can significantly increase the rate of penetration (ROP) and extend PDC bit life for drilling hard and abrasive formation. The knowledge of force response and mechanical specific energy (MSE) for the Stinger PDC cutter is of great importance for improving the cutter's performance and optimizing the hybrid PDC bit design. In this paper, 87 single cutter tests were conducted on the granite. A new method for precisely obtaining the rock broken volume was proposed. The influences of cutting depth, cutting angle, and cutting speed on cutting force and MSE were analyzed. Besides, a phenomenological cutting force model of the Stinger PDC cutter was established by regression of experimental data. Moreover, the surface topography and fracture morphology of the cutting groove and large size cuttings were measured by a 3D profilometer and a scanning electron microscope (SEM). Finally, the rock-breaking mechanism of the Stinger PDC cutter was illustrated. The results indicated that the cutting depth has the greatest influence on the cutting force and MSE, while the cutting speed has no obvious effects, especially at low cutting speeds. As the increase of cutting depth, the cutting force increases linearly, and MSE reduces with a quadratic polynomial relationship. When the cutting angle raises from 10° to 30°, the cutting force increases linearly, and the MSE firstly decreases and then increases. The optimal cutting angle for breaking rock is approximately 20°. The Stinger PDC cutter breaks granite mainly by high concentrated point loading and tensile failure, which can observably improve the rock breaking efficiency. The key findings of this work will help to reveal the rock-breaking mechanisms and optimize the cutter arrangement for the Stinger PDC cutter. 展开更多
关键词 Stinger PDC cutter Cutting force Mechanical specific energy Single cutter tests
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Oxygen Evolution Reaction in Energy Conversion and Storage: Design Strategies Under and Beyond the Energy Scaling Relationship 被引量:6
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作者 Jiangtian Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第7期86-117,共32页
The oxygen evolution reaction(OER)is the essential module in energy conversion and storage devices such as electrolyzer,rechargeable metal–air batteries and regenerative fuel cells.The adsorption energy scaling relat... The oxygen evolution reaction(OER)is the essential module in energy conversion and storage devices such as electrolyzer,rechargeable metal–air batteries and regenerative fuel cells.The adsorption energy scaling relations between the reaction intermediates,however,impose a large intrinsic overpotential and sluggish reaction kinetics on OER catalysts.Developing advanced electrocatalysts with high activity and stability based on non-noble metal materials is still a grand challenge.Central to the rational design of novel and high-efficiency catalysts is the development and understanding of quantitative structure–activity relationships,which correlate the catalytic activities with structural and electronic descriptors.This paper comprehensively reviews the benchmark descriptors for OER electrolysis,aiming to give an in-depth understanding on the origins of the electrocatalytic activity of the OER and further contribute to building the theory of electrocatalysis.Meanwhile,the cutting-edge research frontiers for proposing new OER paradigms and crucial strategies to circumvent the scaling relationship are also summarized.Challenges,opportunities and perspectives are discussed,intending to shed some light on the rational design concepts and advance the development of more efficient catalysts for enhancing OER performance. 展开更多
关键词 Oxygen evolution energy conversion and storage Scaling relationship Catalytic descriptors Lattice oxygen oxidation
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FINITE TIME BLOW UP OF THE SOLUTIONS TO BOUSSINESQ EQUATION WITH LINEAR RESTORING FORCE AND ARBITRARY POSITIVE ENERGY 被引量:2
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作者 nikolay kutev natalia kolkovska milena dimova 《Acta Mathematica Scientia》 SCIE CSCD 2016年第3期881-890,共10页
Finite time blow up of the solutions to Boussinesq equation with linear restoring force and combined power nonlinearities is studied. Sufficient conditions on the initial data for nonexistence of global solutions are ... Finite time blow up of the solutions to Boussinesq equation with linear restoring force and combined power nonlinearities is studied. Sufficient conditions on the initial data for nonexistence of global solutions are derived. The results are valid for initial data with arbitrary high positive energy. The proofs are based on the concave method and new sign preserving functionals. 展开更多
关键词 Boussinesq equation with linear restoring force finite time blow up arbitrary high positive energy combined power nonlinearities sign preserving functionals
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A Study of the Relationship between Air Pollutants and Inversion in the ABL over the City of Lanzhou 被引量:14
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作者 张强 李宏宇 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第4期879-886,共8页
By analyzing the pollutant concentrations over the urban area and over the rural area of the city of Lanzhou, Gansu Province, China, the relationships between the daytime inversion intensity and the pollutant concentr... By analyzing the pollutant concentrations over the urban area and over the rural area of the city of Lanzhou, Gansu Province, China, the relationships between the daytime inversion intensity and the pollutant concentration in the atmospheric boundary layer (ABL) are studied with the consideration of wind speed and direction, potential temperature, specific humidity profiles, pollutant concentration in the ABL, the surface temperature, and global radiation on the ground. It was shown that the daytime inversion is a key factor in controlling air pollution concentration. A clear and positive feedback process between the daytime inversion intensity and the air pollutants over the city was found through the analysis of influences of climatic and environmental factors. The mechanisms by which the terrain and air pollutants affect the formation of the daytime inversion are discussed. The solar radiation as the essential energy source to maintain the inversion is analyzed, as are various out-forcing factors affecting the inversion and air pollutants. At last, a physical frame of relationships of air pollution with daytime inversion and the local and out-forcing factors over Lanzhou is built. 展开更多
关键词 relationship Lanzhou City INVERSION POLLUTANT out-forcing factors
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Mathematical Modeling of the Transfer of Energy Forces from the Engine through Hydro Transmission and Hydro Differential to Executive Bodies 被引量:1
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作者 Farkhod Matmurodov Bozorboy Sobirov +3 位作者 Isomiddin Tulanov Jakhongir Mirzaabdullayev Jamshid Khakimov Oybek Daminov 《World Journal of Mechanics》 2019年第5期105-112,共8页
Mathematically simulated energy transfers from the energy source to the chassis through hydro transmissions and hydro differential. The developed unified mathematical model of a dynamic system allows, at the design st... Mathematically simulated energy transfers from the energy source to the chassis through hydro transmissions and hydro differential. The developed unified mathematical model of a dynamic system allows, at the design stage, of many branched drive mechanisms, including transmission hydraulic and hydraulic differential actuators, to explore dynamic processes and select rational parameters. 展开更多
关键词 energy forceS Dynamic System Many-Branched Mechanism ENGINE HYDRO TRANSMISSION HYDRO DIFFERENTIAL
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Dark Matter and the Energy-Momentum Relationship in a Hydrogen Atom 被引量:1
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作者 Koshun Suto 《Journal of High Energy Physics, Gravitation and Cosmology》 2020年第1期52-61,共10页
Einstein derived the energy-momentum relationship which holds in an isolated system in free space. However, this relationship is not applicable in the space inside a hydrogen atom where there is potential energy. Ther... Einstein derived the energy-momentum relationship which holds in an isolated system in free space. However, this relationship is not applicable in the space inside a hydrogen atom where there is potential energy. Therefore, in 2011, the author derived an energy-momentum relationship applicable to the electron constituting a hydrogen atom. This paper derives that relationship in a simpler way using another method. From this relationship, it is possible to derive the formula for the energy levels of a hydrogen atom. The energy values obtained from this formula almost match the theoretical values of Bohr. However, the relationship derived by the author includes a state that cannot be predicted with Bohr’s theory. In the hydrogen atom, there is an energy level with n = 0. Also, there are energy levels where the relativistic energy of the electron becomes negative. An electron with this negative energy (mass) exists near the atomic nucleus (proton). The name “dark hydrogen atom” is given to matter formed from one electron with this negative mass and one proton with positive mass. Dark hydrogen atoms, dark hydrogen molecules, other types of dark atoms, and aggregates made up of dark molecules are plausible candidates for dark matter, the mysterious type of matter whose true nature is currently unknown. 展开更多
关键词 Einstein’s energy-MOMENTUM relationship Classical Quantum theory Ultra-Low energy Levels DIRAC Relativistic Wave Equation DARK Matter DARK Hydrogen TRIPLET Production
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Zero Strength of the Lorentz Force and Lack of a Classical Energy Radiation in the Bohr's Hydrogen Atom?
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2019年第7期717-724,共8页
It is demonstrated that the Lorentz force acting on the electron particle in the Bohr's hydrogen atom, as well as the classical radiation energy of that atom, tends to be zero on condition both the electric and ma... It is demonstrated that the Lorentz force acting on the electron particle in the Bohr's hydrogen atom, as well as the classical radiation energy of that atom, tends to be zero on condition both the electric and magnetic fields in the atom are considered in a definite quantum state. The ratio of the mentioned fields becomes of importance for discussion of the occurence of the electron spin. 展开更多
关键词 Bohr's Hydrogen Atom Lorentz force CLASSICAL ELECTRON RADIATION energy ELECTRON Spin
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Transport of Relativistic Electrons Scattered by the Coulomb Force and a Thermionic Energy Converter with a Built-in Discharge Tube
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作者 Mitsuaki Nagata 《Journal of Modern Physics》 2021年第12期1708-1720,共13页
A transport equation of momentum for relativistic electrons scattered isotropically was previously reported. Here, a momentum-transport equation for relativistic electrons “scattered anisotropically” by the Coulomb ... A transport equation of momentum for relativistic electrons scattered isotropically was previously reported. Here, a momentum-transport equation for relativistic electrons “scattered anisotropically” by the Coulomb force is inquired into. An ideal plasma consisting of electrons and deuterons is treated again. Also, to raise a generation-ability of a thermionic energy converter, a means of introducing external electric and magnetic fields within “a converter in which an emitter plate and a collector plate face simply each other” is proposed. 展开更多
关键词 Transport of Relativistic Electrons Coulomb force Scattering thermionic energy Converter with Some Supplemental Equipments
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Energy Security and Climate Change in the European Union,China and Latin American Relationships:Major Challenges and Areas of International Cooperation
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作者 Maria Cristina Silva Parejas 《国际展望》 2009年第1期199-216,126,共19页
The author discusses the subject in both ecological and political perspectives based on a most comprehensive,authoritative and updated bibliography.Hence,Latin America and the Caribbean(LAC) is as much diversified as ... The author discusses the subject in both ecological and political perspectives based on a most comprehensive,authoritative and updated bibliography.Hence,Latin America and the Caribbean(LAC) is as much diversified as there are sub-regions and regional organizations in geopolitical and geo-economical terms and often dialectic regarding energy security,climate change and LAC ties with Europeans and China and so is the tripartite relations with the rest of the world so far as energy security and climate cha... 展开更多
关键词 In energy Security and Climate Change in the European Union China and Latin American relationships LAC Security
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Why are muscles strong, and why do they require little energy in eccentric action? 被引量:2
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作者 Walter Herzog 《Journal of Sport and Health Science》 SCIE 2018年第3期255-264,共10页
It is well acknowledged that muscles that are elongated while activated(i.e.,eccentric muscle action)are stronger and require less energy(per unit of force)than muscles that are shortening(i.e.,concentric contraction)... It is well acknowledged that muscles that are elongated while activated(i.e.,eccentric muscle action)are stronger and require less energy(per unit of force)than muscles that are shortening(i.e.,concentric contraction)or that remain at a constant length(i.e.,isometric contraction).Although the cross-bridge theory of muscle contraction provides a good explanation for the increase in force in active muscle lengthening,it does not explain the residual increase in force following active lengthening(residual force enhancement),or except with additional assumptions,the reduced metabolic requirement of muscle during and following active stretch.Aside from the cross-bridge theory,2 other primary explanations for the mechanical properties of actively stretched muscles have emerged:(1)the so-called sarcomere length nonuniformity theory and(2)the engagement of a passive structural element theory.In this article,these theories are discussed,and it is shown that the last of these—the engagement of a passive structural element in eccentric muscle action—offers a simple and complete explanation for many hitherto unexplained observations in actively lengthening muscle.Although by no means fully proven,the theory has great appeal for its simplicity and beauty,and even if over time it is shown to be wrong,it nevertheless forms a useful framework for direct hypothesis testing. 展开更多
关键词 CROSS-BRIDGE theory ECCENTRIC force-length relationship Residual force enhancement TITIN
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Prediction and Analysis of the Force and Shape Parameters in Variable Gauge Rolling 被引量:5
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作者 Yuanming Liu Zhenhua Wang +4 位作者 Tao Wang Jie Sun Xianguang Zheng Dianhua Zhang Qingxue Huang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第4期79-92,共14页
Variable gauge rolling is a new process to obtain a plate for which the thickness changes continuously by continuously and dynamically adjusting the roll gap upward and downward in the rolling process.This technology ... Variable gauge rolling is a new process to obtain a plate for which the thickness changes continuously by continuously and dynamically adjusting the roll gap upward and downward in the rolling process.This technology is an efective method for producing lightweight,low-cost,and economical plates.However,variable gauge rolling is an unsteady process,and the changes in the force and deformation parameters are complex.In this research,based on the minimum energy theory of the variational principle and considering the characteristics of the roll movement and workpiece deformation comprehensively,the internal plastic deformation,friction,shear and tension powers,and the minimum result of the total power functional in upward and downward rolling are obtained with the frst integral and then with a variation of adopting the specifc plastic power and strain rate vector inner product.The analytical results of the deformation and force parameters are also established using the variational method.Then the precision of this model is certifed using the measured values in a medium plate hot rolling plant and the experimental data for Tailor Rolled Blank rolling.Good agreement is found.Additionally,the variation rule of bite angle,neutral angle,and location neutral points are shown,and the change mechanism of the friction parameter on the stress state efect coefcient is given in variable gauge rolling.This research proposes a new mathematical model for rolling process control that provides a scientifc basis and technical support for obtaining an accurate section shape in variable gauge rolling production. 展开更多
关键词 Variable gauge rolling Analytical solution Roll separating force energy method Neutral point
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Virtual Machine Consolidation with Multi-Step Prediction and Affinity-Aware Technique for Energy-Efficient Cloud Data Centers
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作者 Pingping Li Jiuxin Cao 《Computers, Materials & Continua》 SCIE EI 2023年第7期81-105,共25页
Virtual machine(VM)consolidation is an effective way to improve resource utilization and reduce energy consumption in cloud data centers.Most existing studies have considered VM consolidation as a bin-packing problem,... Virtual machine(VM)consolidation is an effective way to improve resource utilization and reduce energy consumption in cloud data centers.Most existing studies have considered VM consolidation as a bin-packing problem,but the current schemes commonly ignore the long-term relationship between VMs and hosts.In addition,there is a lack of long-term consideration for resource optimization in the VM consolidation,which results in unnecessary VM migration and increased energy consumption.To address these limitations,a VM consolidation method based on multi-step prediction and affinity-aware technique for energy-efficient cloud data centers(MPaAF-VMC)is proposed.The proposed method uses an improved linear regression prediction algorithm to predict the next-moment resource utilization of hosts and VMs,and obtains the stage demand of resources in the future period through multi-step prediction,which is realized by iterative prediction.Then,based on the multi-step prediction,an affinity model between the VM and host is designed using the first-order correlation coefficient and Euclidean distance.During the VM consolidation,the affinity value is used to select the migration VM and placement host.The proposed method is compared with the existing consolidation algorithms on the PlanetLab and Google cluster real workload data using the CloudSim simulation platform.Experimental results show that the proposed method can achieve significant improvement in reducing energy consumption,VM migration costs,and service level agreement(SLA)violations. 展开更多
关键词 Cloud computing VM consolidation multi-step prediction affinity relationship energy efficiency
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Calculation and Test of Hitting Force of Firing Bullet on the Bulletproof Helmet 被引量:1
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作者 Jinji, Guo Haoxu, Xing +3 位作者 Gao, Yang Chengbai, Wu Jincai, Pei Zhijian, Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第3期69-76,共8页
In this paper the hit force of firing bullet on bulletproof helmet has been computed and the test device has been described. The device is divided into two parts: 1) The bullet, helmet and mould are in one system, u... In this paper the hit force of firing bullet on bulletproof helmet has been computed and the test device has been described. The device is divided into two parts: 1) The bullet, helmet and mould are in one system, using moment theorem to calculate the hit force; 2) The mould, sensor and support pole are in one system, using the method in reference [1] that measures the dynamic strain and displacement of simulate target of bulletproof clothes. We compute the transfigure energy and momentum energy when hitting the mould, the work done by the sensor and the expend energy of support pole. We get the hit force of helmet using energy balance principle. The result is according with the test and has been used to design the GGK93T bulletproof helmet and other serial products. 展开更多
关键词 Bulletproof helmet Bullet hit force Head mould force sensor Hitting energy
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