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Diagnosis of the Kinetic Energy of the“21·7”Extreme Torrential Rainfall Event in Henan Province,China
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作者 Xiuping YAO Ruoying LI +1 位作者 Xiaohong BAO Qiaohua LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期73-83,共11页
An extreme torrential rain(ETR)event occurred in Henan Province,China,during 18-21 July 2021.Based on hourly rain-gauge observations and ERA5 reanalysis data,the ETR was studied from the perspective of kinetic energy(... An extreme torrential rain(ETR)event occurred in Henan Province,China,during 18-21 July 2021.Based on hourly rain-gauge observations and ERA5 reanalysis data,the ETR was studied from the perspective of kinetic energy(K),which can be divided into rotational wind(V_(R))kinetic energy(K_(R)),divergent wind kinetic energy(K_(D)),and the kinetic energy of the interaction between the divergent and rotational winds(K_(RD)).According to the hourly precipitation intensity variability,the ETR process was divided into an initial stage,a rapid increase stage,and maintenance stage.Results showed that the intensification and maintenance of ETR were closely related to the upper-level K,and most closely related to the upperlevel K_(R),with a correlation coefficient of up to 0.9.In particular,the peak value of hourly rainfall intensity lagged behind the K_(R) by 8 h.Furthermore,diagnosis showed that K transformation from unresolvable to resolvable scales made the ETR increase slowly.The meridional rotational wind(u_(R))and meridional gradient of the geopotential(φ)jointly determined the conversion of available potential energy(APE)to K_(R) through the barotropic process,which dominated the rapid enhancement of K_(R) and then caused the rapid increase in ETR.The transportation of K by rotational wind consumed K_(R),and basically offset the K_(R) produced by the barotropic process,which basically kept K_(R) stable at a high value,thus maintaining the ETR. 展开更多
关键词 extreme torrential rain rotational kinetic energy kinetic energy generation and transport barotropic process
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A nonlinear creep model for surrounding rocks of tunnels based on kinetic energy theorem
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作者 Wenbo Liu Hui Zhou +2 位作者 Shuguang Zhang Shuai Jiang Liu Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第2期363-374,共12页
The initiating condition for the accelerated creep of rocks has caused difficulty in analyzing the whole creep process.Moreover,the existing Nishihara model has evident shortcomings in describing the accelerated creep... The initiating condition for the accelerated creep of rocks has caused difficulty in analyzing the whole creep process.Moreover,the existing Nishihara model has evident shortcomings in describing the accelerated creep characteristics of the viscoplastic stage from the perspective of internal energy to analyze the mechanism of rock creep failure and determine the threshold of accelerated creep initiation.Based on the kinetic energy theorem,Perzyna viscoplastic theory,and the Nishihara model,a unified creep constitutive model that can describe the whole process of decaying creep,stable creep,and accelerated creep is established.Results reveal that the energy consumption and creep damage in the process of creep loading mainly come from the internal energy changes of geotechnical materials.The established creep model can not only describe the viscoelasticeplastic creep characteristics of rock,but also reflect the relationship between rock energy and creep deformation change.In addition,the research results provide a new method for determining the critical point of creep deformation and a new idea for studying the creep model and creep mechanical properties. 展开更多
关键词 Internal energy kinetic energy theorem Perzyna viscoplastic theory Nishihara model Accelerated creep Initiating threshold
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Kinetic Energy Budgets during the Rapid Intensification of Typhoon Rammasun (2014)
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作者 Xin QUAN Xiaofan LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期78-94,共17页
In this study,Typhoon Rammasun(2014)was simulated using the Weather Research and Forecasting model to examine the kinetic energy during rapid intensification(RI).Budget analyses revealed that in the inner area of the ... In this study,Typhoon Rammasun(2014)was simulated using the Weather Research and Forecasting model to examine the kinetic energy during rapid intensification(RI).Budget analyses revealed that in the inner area of the typhoon,the conversion from symmetric divergent kinetic energy associated with the collocation of strong cyclonic circulation and inward flow led to an increase in the symmetric rotational kinetic energy in the lower troposphere.The increase in the symmetric rotational kinetic energy in the mid and upper troposphere resulted from the upward transport of symmetric rotational kinetic energy from the lower troposphere.In the outer area,both typhoon and Earth’s rotation played equally important roles in the conversion from symmetric divergent kinetic energy to symmetric rotational kinetic energy in the lower troposphere.The decrease in the symmetric rotational kinetic energy in the upper troposphere was caused by the conversion to asymmetric rotational kinetic energy through the collocation of symmetric tangential rotational winds and the radial advection of asymmetric tangential rotational winds by radial environmental winds. 展开更多
关键词 Typhoon Rammasun(2014) rapid intensification kinetic energy budget symmetric and asymmetric winds divergent and rotational circulations environmental flows
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Turbulent Kinetic Energy of Flow during Inhale and Exhale to Characterize the Severity of Obstructive Sleep Apnea Patient
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作者 W.M.Faizal C.Y.Khor +4 位作者 Muhammad Nooramin Che Yaakob N.N.N.Ghazali M.Z.Zainon Norliza Binti Ibrahim Roziana Mohd Razi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期43-61,共19页
This paper aims to investigate and present the numerical investigation of airflow characteristics using Turbulent Kinetic Energy(TKE)to characterize the upper airway with obstructive sleep apnea(OSA)under inhale and e... This paper aims to investigate and present the numerical investigation of airflow characteristics using Turbulent Kinetic Energy(TKE)to characterize the upper airway with obstructive sleep apnea(OSA)under inhale and exhale breathing conditions.The importance of TKE under both breathing conditions is that it showan accuratemethod in expressing the severity of flow in sleep disorder.Computational fluid dynamics simulate the upper airway’s airflow via steady-state Reynolds-averaged Navier-Stokes(RANS)with k–ωshear stress transport(SST)turbulencemodel.The three-dimensional(3D)airway model is created based on the CT scan images of an actual patient,meshed with 1.29 million elements using Materialise Interactive Medical Image Control System(MIMICS)and ANSYS software,respectively.High TKE were noticed around the region after the necking(smaller cross-sectional area)during the inhale and exhale breathing.The turbulent kinetic energy could be used as a valuablemeasure to identify the severity of OSA.This study is expected to provide a better understanding and clear visualization of the airflow characteristics during the inhale and exhale breathing in the upper airway of patients for medical practitioners in the OSA research field. 展开更多
关键词 Obstructive sleep apnea breathing disorders real patient CFD turbulent kinetic energy
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Previously Unknown Formulas for the Relativistic Kinetic Energy of an Electron in a Hydrogen Atom
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作者 Koshun Suto 《Journal of Applied Mathematics and Physics》 2023年第4期972-987,共16页
Einstein’s energy-momentum relationship, which holds in an isolated system in free space, contains two formulas for relativistic kinetic energy. Einstein’s relationship is not applicable in a hydrogen atom, where po... Einstein’s energy-momentum relationship, which holds in an isolated system in free space, contains two formulas for relativistic kinetic energy. Einstein’s relationship is not applicable in a hydrogen atom, where potential energy is present. However, a relationship similar to that can be derived. That derived relationship also contains two formulas, for the relativistic kinetic energy of an electron in a hydrogen atom. Furthermore, it is possible to derive a third formula for the relativistic kinetic energy of an electron from that relationship. Next, the paper looks at the fact that the electron has a wave nature. Five more formulas can be derived based on considerations relating to the phase velocity and group velocity of the electron. This paper presents eight formulas for the relativistic kinetic energy of an electron in a hydrogen atom. 展开更多
关键词 Einstein’s energy-Momentum Relationship Relativistic kinetic energy Bohr’s Quantum Condition Potential energy Phase Velocity Group Velocity
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Quantization of the Kinetic Energy of Deterministic Chaos
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作者 Victor A. Miroshnikov 《American Journal of Computational Mathematics》 2023年第1期1-81,共81页
In previous works, the theoretical and experimental deterministic scalar kinematic structures, the theoretical and experimental deterministic vector kinematic structures, the theoretical and experimental deterministic... In previous works, the theoretical and experimental deterministic scalar kinematic structures, the theoretical and experimental deterministic vector kinematic structures, the theoretical and experimental deterministic scalar dynamic structures, and the theoretical and experimental deterministic vector dynamic structures have been developed to compute the exact solution for deterministic chaos of the exponential pulsons and oscillons that is governed by the nonstationary three-dimensional Navier-Stokes equations. To explore properties of the kinetic energy, rectangular, diagonal, and triangular summations of a matrix of the kinetic energy and general terms of various sums have been used in the current paper to develop quantization of the kinetic energy of deterministic chaos. Nested structures of a cumulative energy pulson, an energy pulson of propagation, an internal energy oscillon, a diagonal energy oscillon, and an external energy oscillon have been established. In turn, the energy pulsons and oscillons include group pulsons of propagation, internal group oscillons, diagonal group oscillons, and external group oscillons. Sequentially, the group pulsons and oscillons contain wave pulsons of propagation, internal wave oscillons, diagonal wave oscillons, and external wave oscillons. Consecutively, the wave pulsons and oscillons are composed of elementary pulsons of propagation, internal elementary oscillons, diagonal elementary oscillons, and external elementary oscillons. Topology, periodicity, and integral properties of the exponential pulsons and oscillons have been studied using the novel method of the inhomogeneous Fourier expansions via eigenfunctions in coordinates and time. Symbolic computations of the exact expansions have been performed using the experimental and theoretical programming in Maple. Results of the symbolic computations have been justified by probe visualizations. 展开更多
关键词 The Navier-Stokes Equations Quantization of kinetic energy Deterministic Chaos Elementary Pulson of Propagation Internal Elementary Oscillon Diagonal Elementary Oscillon External Elementary Oscillon Wave Pulson of Propagation Internal Wave Oscillon Diagonal Wave Oscillon External Wave Oscillon Group Pulson of Propagation Internal Group Oscillon Diagonal Group Oscillon External Group Oscillon energy Pulson of Propagation Internal energy Oscillon Diagonal energy Oscillon External energy Oscillon Cumulative energy Pulson
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Features of eddy kinetic energy and variations of upper circulation in the South China Sea 被引量:14
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作者 贺志刚 王东晓 胡建宇 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第2期305-314,共10页
The features of eddy kinetic energy (EKE) and the variations of upper circulation in theSouth China Sea (SCS) are discussed in this paper using geostrophic currents estimated from Maps of Sea Level Anomalies of the TO... The features of eddy kinetic energy (EKE) and the variations of upper circulation in theSouth China Sea (SCS) are discussed in this paper using geostrophic currents estimated from Maps of Sea Level Anomalies of the TOPEX/Poseidon altimetry data. A high EKE center is identified in the southeast of Vietnam coast with the highest energy level 1 400 cm2 ·s^(-2) in both summer and autumn. This high EKE center is caused by the instability of the current axis leaving the coast of Vietnam in summer and the transition of seasonal circulation patterns in autumn. There exists another high EKE region in the northeastern SCS, southwest to Taiwan Island in winter. This high EKE region is generated from the eddy activities caused by the Kuroshio intrusion and accumulates more than one third of the annual EKE, which confirms that the eddies are most active in winter. The transition of upper circulation patterns is also evidenced by the directions of the major axises of velocity variance ellipses between 10?and 14.5°N, which supports the model results reported before. 展开更多
关键词 The South China Sea eddy kinetic energy TOPEX/POSEIDON upper circulation altimeter data
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Seasonal variation of eddy kinetic energy in the South China Sea 被引量:11
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作者 WANG Hui WANG Dakui +2 位作者 LIU Guimei WU Huiding LI Ming 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第1期1-15,共15页
Mesoscale eddy activity and its modulation mechanism in the South China Sea (SCS) are inves- tigated with newly reprocessed satellite altimetry observations and hydrographic data. The eddy kinetic energy (EKE) lev... Mesoscale eddy activity and its modulation mechanism in the South China Sea (SCS) are inves- tigated with newly reprocessed satellite altimetry observations and hydrographic data. The eddy kinetic energy (EKE) level of basin-wide averages show a distinct seasonal cycle with the maximum in August-December and the minimum in February-May. Furthermore, the seasonal pattern of EKE in the basin is dominated by region offshore of central Vietnam (OCV), southwest of Taiwan Island (SWT), and southwest of Luzon (SWL), which are also the breeding grounds of mesoscale eddies in the SCS. Instability theory analysis suggests that the seasonal cycle of EKE is modulated by the baroclinic instability of the mean flow. High eddy growth rate (EGR) is found in the active eddy regions. Vertical velocity shear in the upper 50-500 m is crucial for the growth of baroclinic instability, leading to seasonal EKE evolution in the SCS. 展开更多
关键词 South China Sea eddy kinetic energy baroclinic instability vertical shear
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Improved Soft Abrasive Flow Finishing Method Based on Turbulent Kinetic Energy Enhancing 被引量:8
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作者 Jun LI Shiming JI Dapeng TAN 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期301-309,共9页
Soft abrasive flow(SAF) finishing can process the irregular geometric surfaces, but with the matter of low processing efficiency. To address the issue, an improved SAF finishing method based on turbulent kinetic ene... Soft abrasive flow(SAF) finishing can process the irregular geometric surfaces, but with the matter of low processing efficiency. To address the issue, an improved SAF finishing method based on turbulent kinetic energy enhancing is proposed. A constrained flow passage with serration cross-section is constructed to increase the turbulence intensity. Taking the constrained flow passage as the objective, a two-phase fluid dynamic model is set up by using particle trajectory model and standard k-ε turbulence model, and the flow field characteristics of the flow passage are acquired. The numerical results show that the serration flow passage can enhance the turbulence intensity, uniform the particles distribution, and increase the particle concentration near the bottom wall. The observation results by particle image velocimetry(PIV) show that the internal vortex structures are formed in flow passage, and the abrasive flow takes on turbulence concentrating phenomenon in near-wall region. The finishing experiments prove that the proposed method can obtain better surface uniformity, and the processing efficiency can be improved more 35%. This research provides an abrasive flow modeling method to reveal the particle motion regulars, and canoffer references to the technical optimization of fluid-based precision processing. 展开更多
关键词 Soft abrasive flow Serration flow passage ·kinetic energy enhancing Particle image velocimetry
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Turbulence Intensity and Turbulent Kinetic Energy Parameters over a Heterogeneous Terrain of Loess Plateau 被引量:5
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作者 YUE Ping ZHANG Qiang +2 位作者 WANG Runyuan LI Yaohui WANG Sheng 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第9期1291-1302,共12页
A deep understanding of turbulence structure is important for investigating the characteristics of the atmospheric boundary layer,especially over heterogeneous terrain.In the present study,turbulence intensity and tur... A deep understanding of turbulence structure is important for investigating the characteristics of the atmospheric boundary layer,especially over heterogeneous terrain.In the present study,turbulence intensity and turbulent kinetic energy(TKE)parameters are analyzed for different conditions with respect to stability,wind direction and wind speed over a valley region of the Loess Plateau of China during December 2003 and January 2004.The purpose of the study is to examine whether the observed turbulence intensity and TKE parameters satisfy Monin–Obukhov similarity theory(MOST),and analyze the wind shear effect on,and thermal buoyancy function of,the TKE,despite the terrain heterogeneity.The results demonstrate that the normalized intensity of turbulence follows MOST for all stability in the horizontal and vertical directions,as well as the normalized TKE in the horizontal direction.The shear effect of the wind speed in the Loess Plateau region is strong in winter and could enhance turbulence for all stability conditions.During daytime,the buoyancy and shear effect together constitute the generation of TKE under unstable conditions.At night,the contribution of buoyancy to TKE is relatively small,and mechanical shearing is the main production form of turbulence. 展开更多
关键词 heterogeneous terrain turbulence intensity turbulent kinetic energy Monin–Obukhov similarity function
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Eddy Kinetic Energy Study of the Snowstorm over Southern China in January 2008 被引量:2
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作者 ZUO Qunjie GAO Shouting L Daren 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第4期972-984,共13页
The energetics of the third stage of a snowstorm over China was analyzed using ECWMF data.The analysis of the energy budget for the Middle East trough and the western Pacific trough that developed toward China on 25-2... The energetics of the third stage of a snowstorm over China was analyzed using ECWMF data.The analysis of the energy budget for the Middle East trough and the western Pacific trough that developed toward China on 25-28 January 2008 showed the advection of the geopotential by the ageostrophic wind to be both a crucial source and the primary sink of the eddy kinetic energy centers associated with the troughs.The magnitudes of the energy conversion terms,interaction kinetic energy conversion and baroclinic conversion,were too small to explain the development of the energy centers and the jet streaks.The energy centers gained energy at their entrance regions via the convergence of the ageostrophic geopotential fluxes,and then lost energy at their exit regions by the same fluxes.At the entrance regions,the fluxes converged,increasing the geopotential gradient,which generated a stronger geostrophic wind and higher kinetic energy,resulting in an ascending motion in this area.When the troughs moved to China,the ascending motion caused by the convergence of the fluxes at entrance region intensified the snowstorms over central and southern China. 展开更多
关键词 eddy kinetic energy ageostrophic geopotential flux snowstorms jet streaks
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Machine Learning Kinetic Energy Functional for a One-Dimensional Periodic System 被引量:1
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作者 任宏斌 王磊 戴希 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第5期1-6,共6页
Kinetic energy(KE) functional is crucial to speed up density functional theory calculation. However, deriving it accurately through traditional physics reasoning is challenging. We develop a generally applicable KE fu... Kinetic energy(KE) functional is crucial to speed up density functional theory calculation. However, deriving it accurately through traditional physics reasoning is challenging. We develop a generally applicable KE functional estimator for a one-dimensional (1D) extended system using a machine learning method. Our end-to-end solution combines the dimensionality reduction method with the Gaussian process regression, and simple scaling method to adapt to various 1D lattices. In addition to reaching chemical accuracy in KE calculation, our estimator also performs well on KE functional derivative prediction. Integrating this machine learning KE functional into the current orbital free density functional theory scheme is able to provide us with expected ground state electron density. 展开更多
关键词 RED GAUSSIAN DFT Machine Learning kinetic energy Functional for a One-Dimensional Periodic System
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KELEA (Kinetic Energy Limiting Electrostatic Attraction) Can Markedly Improve the Performance of Gasoline and Diesel Fuels in Power Generation and in Transportation 被引量:3
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作者 W. John Martin 《Journal of Transportation Technologies》 2016年第3期148-154,共7页
The combustion (burning) of hydrocarbon fuels comprises oxygen mediated breaking of the carbon to carbon and carbon to hydrogen chemical bonds, leading to the formation of oxygen to carbon and oxygen to hydrogen bonds... The combustion (burning) of hydrocarbon fuels comprises oxygen mediated breaking of the carbon to carbon and carbon to hydrogen chemical bonds, leading to the formation of oxygen to carbon and oxygen to hydrogen bonds;primarily as carbon dioxide and water, respectively. The oxygen gas molecules yield considerable energy during the conversion to carbon and hydrogen bound oxygen atoms. The net energy derived from hydrocarbon combustion is normally regarded as being fully converted into heat, as a form of kinetic energy. In industrial processes, some of the resulting heat is used to raise the temperature of other materials, including water for power generation. Combustion derived heat is also used to provide a localized increase in kinetic energy (pressure) of gaseous molecules that can be directly converted into mechanical work. This is the principle of combustion driven transportation and many other power generating engines. An emerging concept is that fluids can also possess a transferrable form of kinetic energy that is unrelated to heat. This newly proposed fluid associated, non-thermal kinetic energy is derived from the environment force termed KELEA (Kinetic Energy Limiting Electrostatic Attraction). KELEA results in the loosening of the hydrogen bonding between liquid molecules and probably also imparts added motion to the molecules. It is proposed that this added non-thermal kinetic energy is carried over into the combustion products, which can consequently yield increased mechanical work. KELEA also seemingly allows for more complete combustion with reduced levels of unburnt hydrocarbons. KELEA activation of liquid fuels can be accomplished using KELEA attracting and transmitting compounds, including activated fluids, either added into or placed in close proximity to the fuel. KELEA activation of fuels, including gasoline and diesel, provides a simple method to significantly improve the efficiency of their use in power generation and in transportation. The studies are relevant to reducing the current worldwide levels of hydrocarbon usage and environmental pollution. 展开更多
关键词 Kiko Mojo GASOLINE DIESEL Combustion KELEA kinetic energy SOLITON Climate Change
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Structure and Propagation Characteristics of Climatological Mean Kinetic Energy of Disturbance of Intraseasonal Oscillation in Asian Summer Monsoon Zone 被引量:1
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作者 GUO Ji-bing CHEN Wei-min XU Jie 《Meteorological and Environmental Research》 CAS 2011年第6期6-10,共5页
[Objective] The research aimed to study the structure and propagation characteristics of climatological mean kinetic energy of disturbance of intraseasonal oscillation in Asian summer monsoon zone. [Method] When South... [Objective] The research aimed to study the structure and propagation characteristics of climatological mean kinetic energy of disturbance of intraseasonal oscillation in Asian summer monsoon zone. [Method] When South China Sea monsoon started to break out, the kinetic energy of intraseasonal oscillation disturbance in the monsoon zone was analyzed, especially the researches about the variation of South China Sea monsoon, the development of Indian monsoon and the advancement of East Asian monsoon. [Result] The developed process of Asian summer monsoon had the close relationship with the kinetic energy activity of 30-60 d low-frequency oscillation disturbance. The kinetic energy of disturbance explained the eruption, occurrence, development and termination of monsoon from the energy angle. It was found that the kinetic energy of disturbance in Arabian Sea zone, Bay of Bengal and South China Sea area was the strongest, especially in Arabian Sea zone. It illustrated that Arabian Sea zone (Somali jet) was the biggest energy source of Asian monsoon. The starting mark of monsoon eruption in the whole Asia was the abrupt eruption of South China Sea monsoon. The eruption of South China Sea monsoon in the middle dekad of May was the westward transmission result of kinetic energy of disturbance on the east sea surface of Philippines. The kinetic energy of disturbance in East Asian monsoon zone had the seasonal northward advancement in summer. The high kinetic energy center of disturbance in Indian monsoon zone changed from one to two. They were respectively in Arabian Sea and Bay of Bengal. [Conclusion] The research provided the theory basis for analyzing the atmospheric intraseasonal oscillation. 展开更多
关键词 Intraseasonal disturbance oscillation Asian summer monsoon Climatological average season kinetic energy of disturbance China
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KELEA (Kinetic Energy Limiting Electrostatic Attraction) Offers an Alternative Explanation to Existing Concepts Regarding Wave-Particle Duality, Cold Fusion and Superconductivity 被引量:4
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作者 W. John Martin 《Journal of Modern Physics》 2016年第15期1995-2007,共13页
Existing explanations for several major phenomena in physics may need to be reconsidered in light of the description of a natural force termed KELEA (kinetic energy limiting electrostatic attraction). Three examples a... Existing explanations for several major phenomena in physics may need to be reconsidered in light of the description of a natural force termed KELEA (kinetic energy limiting electrostatic attraction). Three examples are selected for discussion in this paper: i) The proposed wave-particle duality of electrons;ii) cold fusion;and iii) superconductivity. The current interpretations of these enigmatic concepts are incomplete and not fully validated by scientific methods. The observations underlying these processes are seemingly consistent with KELEA acting as a repelling force between opposite electrical charges. Relatively simple experiments can be designed to either confirm or exclude KELEA in these and in various other currently perplexing physical phenomena. 展开更多
关键词 KELEA kinetic energy Limiting Electrostatic Attraction LENR Low energy Nuclear Reaction Wave-Particle Duality Double Slit Experiment Cold Fusion DEUTERIUM Palladium SUPERCONDUCTIVITY Condensed Matter Nuclear Science Brown’s Gas ELECTROLYSIS Activated Water
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Gedanken Experiment Examining How Kinetic Energy Would Dominate Potential Energy, in Pre-Planckian Space-Time Physics, and Allow Us to Avoid the BICEP 2 Mistake 被引量:5
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第1期75-82,共8页
We use Padmabhan’s “Invitation to Astrophysics” formalism of a scalar field evolution of the early universe, from first principles, to show something which seems counter intuitive. How could, just before inflation,... We use Padmabhan’s “Invitation to Astrophysics” formalism of a scalar field evolution of the early universe, from first principles, to show something which seems counter intuitive. How could, just before inflation, kinetic energy be larger than potential energy in pre-Planckian physics, and what physics mechanism is responsible for the Planckian physics result that Potential energy is far larger than kinetic energy. This document answers that question, as well as provides a mechanism for the dominance of kinetic energy in pre-Planckian space-time, as well as its reversal in the Planckian era of cosmology. The kinetic energy is proportional to , with initial degrees of freedom, and T the initial temperature just before the onset of inflation. Our key assumption is the smallness of curvature, as given in the first equation, which permits adoption of the Potential energy and Kinetic energy formalism used, in the Planckian and pre-Planckian space-time physics. Interpretation of this result, if done correctly, will be able to allow a correct distinguishing of relic gravitational waves, as to avoid the BICEP 2 pickup of galactic dust as a false relic Gravitational wave signal, as well as serve as an investigative template as to if quantum gravity is embedded in a deterministic dissipative system, as cited in the conclusion. 展开更多
关键词 Geddanken Experiment kinetic energy Potential energy
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Kinetic Energy Recovery from the Chimney Flue Gases Using Ducted Turbine System
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作者 Harjeet S.Mann Pradeep K.Singh 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期472-482,共11页
An innovative idea of extracting kinetic energy from man-made wind resources using ducted turbine system for on-site power generation is introduced in this paper. A horizontal axis ducted turbine is attached to the to... An innovative idea of extracting kinetic energy from man-made wind resources using ducted turbine system for on-site power generation is introduced in this paper. A horizontal axis ducted turbine is attached to the top of the chimney to harness the kinetic energy of flue gases for producing electricity. The turbine system is positioned beyond the chimney outlet, to avoid any negative impact on the chimney performance. The convergentdivergent duct causes increase in the flue gas velocity and hence enhances the performance of the turbine. It also acts as a safety cover to the energy recovery system. The results from the CFD based simulation analysis indicate that sig- nificant power 34 kW can be harnessed from the chimney exhaust. The effect of airfoils NACA4412 and NACA4416 and the diffuser angle on the power extraction by the energy recovery system using a 6-bladed ducted turbine has been studied with the CFD simulation. It is observed that the average flue gas velocity in the duct section at the throat is approximately twice that of the inlet velocity, whereas maximum velocity achieved is 2.6 times the inlet velocity. The simulated results show that about power may be extracted from the chimney flue gases of 660 MW power plant. The system can be retrofitted to existing chimneys of thermal power plants, refineries and other industries. 展开更多
关键词 Chimney flue gases energy recovery system ·kinetic energy Ducted turbine CFD
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Estimation of Turbulent Kinetic Energy Dissipation Rate in the Bottom Boundary Layer of the Pearl River Estuary
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作者 刘欢 吴超羽 任杰 《China Ocean Engineering》 SCIE EI 2011年第4期669-678,共10页
A structure function approach is applied to estimate the turbulent kinetic energy (TKE) dissipation rate in the bottom boundary layer of the Pearl River Estuary (PRE). Simultaneous measurements with an acoustic Do... A structure function approach is applied to estimate the turbulent kinetic energy (TKE) dissipation rate in the bottom boundary layer of the Pearl River Estuary (PRE). Simultaneous measurements with an acoustic Doppler velocimeter (ADV) supplied independent data for the verification of the structure function method. The results show that, 1) the structure function approach is reliable and successfully applied method to estimate the TKE dissipation rate. The observed dissipation rates range between 8.3 ×10^-4 W/kg and 4.9× 10^-6 W/kg in YM01 and between 3.4×10^-4 W/kg and 4.8×10^-7 W/kg in YM03, respectively, while exhibiting a strong quarter-diurnal variation. 2) The balance between the shear production and viscous dissipation is better achieved in the straight river. This first-order balance is significantly broken in the estuary by non-shear production/dissipation due to wave-induced fluctuations. 展开更多
关键词 structure function turbulent kinetic energy dissipation rate bottom boundary layer Pearl River Estuary
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Seasonal variations of eddy kinetic energy fl ux in the South Indian Countercurrent region
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作者 CHEN Zhongqian WANG Faming +1 位作者 ZHENG Jian YANG Yuxing 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第5期1464-1475,共12页
The inverse cascade fl ux of kinetic energy(KE)and its length scale in the South Indian Countercurrent(SICC)region were investigated using 24-year satellite altimeter daily data from 1993–2016.The evolution of the ed... The inverse cascade fl ux of kinetic energy(KE)and its length scale in the South Indian Countercurrent(SICC)region were investigated using 24-year satellite altimeter daily data from 1993–2016.The evolution of the eddy life cycle in the SICC was presented systemically.It was found that the arrest and inject scales of inverse cascade were within the baroclinic most unstable scale and observed energy-containing eddy scale.The seasonal cycle of the arrest scale,inject scale,and amplitude of the inverse cascade were compared with the eddy kinetic energy seasonal cycle,which revealed a 1.5-month lag of the eddy kinetic energy to the vertical shear of zonal velocity,implying the existence of nonlinear processes during the eddy growth phase.Meanwhile,the anisotropy of the inverse cascade indicated that kinetic energy might be transferred from meridional motions to zonal motions,which is probably caused byβeff ect.These results would be benefi cial for a better understanding of the KE transfer processes in the SICC region. 展开更多
关键词 mesoscale eddies spectral kinetic energy fl ux inverse cascade South Indian Countercurrent(SICC)
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On the Seasonal Transition and the Interannual Variability in Global Kinetic Energy at 500 hPa, Accompanied withAnomalies of Energy during the 1982 / 83 ENSO
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作者 仇永炎 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第2期248-256,共9页
Utilizing the material of monthly means of the three primary kinetic energy modes over the whote globe at 500 hPa during the nine years of 1980-1988, both the rapid seasonal changes and the interannual variability in ... Utilizing the material of monthly means of the three primary kinetic energy modes over the whote globe at 500 hPa during the nine years of 1980-1988, both the rapid seasonal changes and the interannual variability in tie general circulation in terms of the energy modes have been investigated, with special attention paid to the unusual year 1983, Two main results are obtained. One, there are remarkable seasonal rapid changes over the Northern Hemisphere, occurring ganerally in April and October. The other, among the nine years of 1980-1988, 1983 is the only one with unusual energy modes and remarkably abnormal seasonal changes. 展开更多
关键词 Accompanied withAnomalies of energy during the 1982 On the Seasonal Transition and the Interannual Variability in Global kinetic energy at 500 hPa SSTA ENSO
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