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Warp Drive with Positive Energy 被引量:2
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作者 Yosef Joseph Segman 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第3期906-913,共8页
Space and time traveling is one of the humanity’s most fascinating and challenging topics. The speed limitation makes space traveling highly difficult. Therefore, discovering the warp drive mechanism intrigued humani... Space and time traveling is one of the humanity’s most fascinating and challenging topics. The speed limitation makes space traveling highly difficult. Therefore, discovering the warp drive mechanism intrigued humanity to travel in space and time. Miguel Alcubierre proposed a model for warp drive. However, the energy density driven from the Alcubierre warp drive model turns to be negative everywhere. Erik Lentz proposed a shifting vector field in which we shall show that shifting vector field with appropriate spaceship geometry may provide positive energy density for warp drive. Further, we suggest looking at the spaceship geometry as a mother wavelet function with shifting, scaling, and rotation operations that may provide additional positive energy density. This sort of design requires a flexible fuselage that can be stretched and rotated. 展开更多
关键词 Warp Drive Alcubierre positive energy Coordinate Transformation Wavelete
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THEORETICAL AND NUMERICAL STUDY OF THE BLOW UP IN A NONLINEAR VISCOELASTIC PROBLEM WITH VARIABLE-EXPONENT AND ARBITRARY POSITIVE ENERGY
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作者 Ala A.TALAHMEH Salim A.MESSAOUDI Mohamed ALAHYANE 《Acta Mathematica Scientia》 SCIE CSCD 2022年第1期141-154,共14页
In this paper,we consider the following nonlinear viscoelastic wave equation with variable exponents:utt-△u+∫_(0)^(t)g(t-τ)△u(x,τ)dτ+μut=|u|^(p(x)-2)-u,whereμis a nonnegative constant and the exponent of nonli... In this paper,we consider the following nonlinear viscoelastic wave equation with variable exponents:utt-△u+∫_(0)^(t)g(t-τ)△u(x,τ)dτ+μut=|u|^(p(x)-2)-u,whereμis a nonnegative constant and the exponent of nonlinearity p(·)and g are given functions.Under arbitrary positive initial energy and specific conditions on the relaxation function g,we prove a finite-time blow-up result.We also give some numerical applications to illustrate our theoretical results. 展开更多
关键词 nonlinear damping blow up finite time variable nonlinearity arbitrary positive energy
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The positive energy conjecture for a class of AHM metrics on R^(2)×T^(n-2)
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作者 Zhuobin Liang Xiao Zhang 《Science China Mathematics》 SCIE CSCD 2023年第5期1041-1052,共12页
We prove the positive energy conjecture for a class of asymptotically Horowitz-Myers(AHM)metrics on R^(2)×T^(n-2).This generalizes the previous results of Barzegar et al.(2020)as well as Liang and Zhang(2020).
关键词 positive energy conjecture asymptotically Horowitz-Myers metrics asymptotically local hyperbolic manifolds
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Community microgrid:an approach towards positive energy community in an urban area of Dhaka,Bangladesh
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作者 Mohammad Zeyad S.M.Masum Ahmed +1 位作者 Sayeed Hasan Dewan Mahnaaz Mahmud 《Clean Energy》 EI CSCD 2023年第4期926-939,共14页
The pollution and toxic greenhouse gases produced by fossil fuel combustion are troubling as global energy demand continues to rise.To mitigate the consequences of global warming,a transition to sustainable energy sou... The pollution and toxic greenhouse gases produced by fossil fuel combustion are troubling as global energy demand continues to rise.To mitigate the consequences of global warming,a transition to sustainable energy sources is necessary.This manuscript presents a feasible community microgrid design in Hazaribagh,Dhaka based on meteorological data that leads to photovoltaic installation on the rooftop of a local community building.This study shows a microgrid design of a system with the lowest cost of energy and a large renewable fraction,which is analysed using the HOMER Pro software.Using real-time data,analysis of the system cost,cost of energy,renewable fraction,unmet load,energy purchased and energy sold is discussed.A suitable case for electrification is also identified and presented for the selected community.The proposed case yields a cost of energy of$0.0357/kWh,which is 52%less than the current tariff rate,with a 70%renewable fraction.This study will provide people in this community with more green energy at a lower cost;in addition,this designed microgrid sells additional energy to the grid to avoid possible power outages.The potential for a positive energy community is also investigated in terms of energy consumption and renewable output of the planned microgrid. 展开更多
关键词 cost of energy MICROGRID positive energy community renewable fraction
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Strategic Position and Roadmap of China's Renewable Energy
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作者 Huang Qili Northeast Power Grid Zhu Li 《Electricity》 2009年第4期34-40,共7页
Fast-growing economy imposing higher requirement for energy industry During the "Tenth Five-Year Plan" period,China's GDP grew at an average annual rate of 9.5%,and correspondingly the total volume of en... Fast-growing economy imposing higher requirement for energy industry During the "Tenth Five-Year Plan" period,China's GDP grew at an average annual rate of 9.5%,and correspondingly the total volume of energy consumption grew at an average annual rate of 10.5%. 展开更多
关键词 Strategic Position and Roadmap of China’s Renewable energy
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具退化非局部阻尼和源项的非线性耦合粘弹性波方程组解的指数增长性
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作者 刘烁 张宏伟 呼青英 《Chinese Quarterly Journal of Mathematics》 2021年第2期210-220,共11页
This paper is concerned with a system of nonlinear viscoelastic wave equations with degenerate nonlocal damping and memory terms.We will prove that the energy associated to the system is unbounded.In fact,it will be p... This paper is concerned with a system of nonlinear viscoelastic wave equations with degenerate nonlocal damping and memory terms.We will prove that the energy associated to the system is unbounded.In fact,it will be proved that the energy will grow up as an exponential function as time goes to infinity,provided that the initial data are positive initial energy. 展开更多
关键词 Exponential growth Nonlocal damping positive initial energy Viscoelastic wave equations
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Dark Matter Creation and Anti-Gravity Acceleration of the Expanding Universe
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作者 F. C. Hoh 《Journal of Modern Physics》 2021年第3期139-160,共22页
Dark matter is identified as negative relative energy between quarks in proton and is generated in cold hydrogen gas with pressure gradient in gravitational field. Positive relative energy PRE can be generated between... Dark matter is identified as negative relative energy between quarks in proton and is generated in cold hydrogen gas with pressure gradient in gravitational field. Positive relative energy PRE can be generated between quarks in protons in cold hydrogen gas in outskirts of the universe. The mechanisms for such creation of dark matter and PRE are reviewed and updated in greater detail and clearer manner. The so-generated dark matter in a galaxy can account for the galaxy’s rotation curve. Star formation in this galaxy uses up the hydrogen atoms and thereby reduces its dark matter content. Dark matter created in intergalactic hydrogen gas can form filaments. In a hypothetical model of the universe, a hydrogen atom with a small amount of negative relative energy or dark matter at the outskirts of this universe can via collisions with other atoms turn into one with a small positive relative energy PRE. Once such a sign change takes place, gravitational attraction switches to anti-gravity repulsion unopposed by any pressure gradient. This leads to a “run away” hydrogen atom moving away from the mass center of the universe and provides a basic mechanism for the accelerating expansion of the universe. This theoretical expansion and the measured redshift data are both compatible with the conception of an acceleratingly expanding universe and complement each other. But they cannot verify each other directly because the present model has been constructed for purposes different from those of the measurements. But it can be shown that both approaches do support each other qualitatively under certain circumstances for small velocities. Dark matter and PRE in the present model are not foreign objects like WIMPs and dark energy-cosmological constant but can only be created in cold hydrogen gas in gravitational field. To achieve this, infrequent collisions among the hydrogen atoms must take place. Dark matter was created first and can eventually later evolve into PRE in the outskirts of the universe and in the intergalactic void. Dark matter and PRE will disappear if the hydrogen atom carrying them becomes ionized as in stars. 展开更多
关键词 Relative energy between Quarks Scalar Strong Interaction Hadron Theory SSI Negative Relative energy Dark Matter positive Relative energy PRE Anti-Gravity Repulsion Universe Expansion Proton Orbit Hubble’s Law
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China(Life Sciences)》 SCIE CAS 2008年第11期1054-1054,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and ex-pand research in the areas of Physical Energy, Chemical Energy, Bio-energy, Energy Efficiency and Energy Econom-i... The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and ex-pand research in the areas of Physical Energy, Chemical Energy, Bio-energy, Energy Efficiency and Energy Econom-ics. SER-XMU is seeking senior scientists and experienced engineers to serve as Thrust Leaders and Principal Inves- 展开更多
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China(Life Sciences)》 SCIE CAS 2009年第5期500-500,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy, Bioenergy, Energy Efficiency and Energy Econom-
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China(Life Sciences)》 SCIE CAS 2009年第1期96-96,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007,to consolidate and expand
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2008年第11期1774-1774,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy, Bio-energy, Energy Efficiency and Energy Economics... The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy, Bio-energy, Energy Efficiency and Energy Economics. SER-XMU is seeking senior scientists and experi-enced engineers to serve as Thrust Leaders and Principal Investigators. 展开更多
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2009年第5期808-808,共1页
The School of Energy Research at Xiamen University(SER-XMU)was founded in 2007,to consolidate and expand research in the areas of Physical Energy,Chemical Energy,Bio-energy,Energy Efficiency and Energy Economics.
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China(Life Sciences)》 SCIE CAS 2009年第3期308-308,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007,to consolidate and
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China Chemistry》 SCIE EI CAS 2008年第12期1256-1256,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy,
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2009年第1期158-158,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007,to consolidate and expand research in the areas of Physical Energy,Chemical Energy,Bio-energy,Energy Efficiency and Energy Economics.
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2009年第3期488-488,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy, Bio-energy, Energy Efficiency and Energy Economics... The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy, Bio-energy, Energy Efficiency and Energy Economics. SER-XMU is seeking senior scientists and experienced engineers to serve as Thrust Leaders and Principal Investiga- 展开更多
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China Chemistry》 SCIE EI CAS 2008年第11期1140-1140,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy,Bio-energy, Energy Efficiency and Energy Economics.... The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy,Bio-energy, Energy Efficiency and Energy Economics. SER-XMU is seeking senior scientists and 展开更多
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China Chemistry》 SCIE EI CAS 2009年第5期698-698,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy,
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
原文传递
Open Positions for Senior Scientists and Engineers in School of Energy Research at Xiamen University
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《Science China Chemistry》 SCIE EI CAS 2009年第1期116-116,共1页
The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy, Bio-energy, Energy Efficiency and Energy Economics... The School of Energy Research at Xiamen University (SER-XMU) was founded in 2007, to consolidate and expand research in the areas of Physical Energy, Chemical Energy, Bio-energy, Energy Efficiency and Energy Economics. SER-XMU is seeking senior 展开更多
关键词 SCHOOL Open Positions for Senior Scientists and Engineers in School of energy Research at Xiamen University
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Remarks on Blow-Up Phenomena in p-Laplacian Heat Equation with Inhomogeneous Nonlinearity
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作者 ALZAHRANI Eadah Ahma MAJDOUB Mohamed 《Journal of Partial Differential Equations》 CSCD 2021年第1期42-50,共9页
We investigate the p-Laplace heat equation ut-△_(p)u=ζ(t)f(u)in a bounded smooth domain.Using differential-inequality arguments,we prove blow-up results under suitable conditions onζ,f,and the initial datum u_(0).W... We investigate the p-Laplace heat equation ut-△_(p)u=ζ(t)f(u)in a bounded smooth domain.Using differential-inequality arguments,we prove blow-up results under suitable conditions onζ,f,and the initial datum u_(0).We also give an upper bound for the blow-up time in each case. 展开更多
关键词 Parabolic problems p-Laplacian equation BLOW-UP positive initial energy
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