In this paper we have investigated the reflection and the transmission of a system of two symmetric circular-arc-shaped thin porous plates submerged in deep water within the context of linear theory. The hypersingular...In this paper we have investigated the reflection and the transmission of a system of two symmetric circular-arc-shaped thin porous plates submerged in deep water within the context of linear theory. The hypersingular integral equation technique has been used to analyze the problem mathematically. The integral equations are formulated by applying Green＇s integral theorem to the fundamental potential function and the scattered potential function into a suitable fluid region, and then using the boundary condition on the porous plate surface. These are solved approximately using an expansion-cure-collocation method where the behaviour of the potential functions at the tips of the plates have been used. This method ultimately produces a very good numerical approximation for the reflection and the transmission coefficients and hydrodynamic force components. The numerical results are depicted graphically against the wave number for a variety of layouts of the arc. Some results are compared with known results for similar configurations of dual rigid plate systems available in the literature with good agreement.展开更多
Through the 5-channel SWAES digital full waveform AE detector, the paper dealt with the fracture process of coal and rock samples under uniaxial compression. Using wavelet operations of multi-scale discrete analysis t...Through the 5-channel SWAES digital full waveform AE detector, the paper dealt with the fracture process of coal and rock samples under uniaxial compression. Using wavelet operations of multi-scale discrete analysis the pulses of a particular time period （points） and the space domain signal by numerical method were gotten, and the paper concluded that the signal singularity in load rupture had closely relations with fracture and uniaxial compression. The detected position and the actual breaking point only differed at one sample point, the relative error was 6.82%, and there was no accumulative error. Thus it provided an effective method to solve the problem of instability analysis of the signal singularity detection and coal-rock compression failure in the whole process.展开更多
The authors consider the multidimensional aggregation equation tp-div（p K＊ ρ） = 0 in which the radially symmetric attractive interaction kernel has a mild singularity at the origin （Lipschitz or better）, and rev...The authors consider the multidimensional aggregation equation tp-div（p K＊ ρ） = 0 in which the radially symmetric attractive interaction kernel has a mild singularity at the origin （Lipschitz or better）, and review recent results on this problem concerning well-posedness of nonnegative solutions and finite time blowup in multiple space dimensions depending on the behavior of the kernel at the origin. The problem with bounded initial data, data in L^p ∩ L^1, and measure solutions are also considered.展开更多
The color-flavor locked(CFL) strangelets have been investigated in a new quark model with linear confinement and one-gluon-exchange interactions.Considering Coulomb energy,we have studied the properties of three kinds...The color-flavor locked(CFL) strangelets have been investigated in a new quark model with linear confinement and one-gluon-exchange interactions.Considering Coulomb energy,we have studied the properties of three kinds of CFL strangelets,namely,positively charged,negatively charged and nearly neutral CFL strangelets.It is found that the one-gluon-exchange effect lowers the energy of a strangelet considerably and thus makes it much more stable than without considering the effect.The charge of a positive strangelet is larger than 0.15A 2/3 with A being the baryon number,but smaller than that in bag model.The charge of a negatively charged or nearly neutral CFL strangelet is nearly proportional to A 1/3.展开更多
基金Partially Supported by the Department of Science and Technology Through a Research Grant to RG(No.SR/FTP/MS-020/2010)
文摘In this paper we have investigated the reflection and the transmission of a system of two symmetric circular-arc-shaped thin porous plates submerged in deep water within the context of linear theory. The hypersingular integral equation technique has been used to analyze the problem mathematically. The integral equations are formulated by applying Green＇s integral theorem to the fundamental potential function and the scattered potential function into a suitable fluid region, and then using the boundary condition on the porous plate surface. These are solved approximately using an expansion-cure-collocation method where the behaviour of the potential functions at the tips of the plates have been used. This method ultimately produces a very good numerical approximation for the reflection and the transmission coefficients and hydrodynamic force components. The numerical results are depicted graphically against the wave number for a variety of layouts of the arc. Some results are compared with known results for similar configurations of dual rigid plate systems available in the literature with good agreement.
基金Supported by the National Natural Science Foundation of China （51174157, 51174158）
文摘Through the 5-channel SWAES digital full waveform AE detector, the paper dealt with the fracture process of coal and rock samples under uniaxial compression. Using wavelet operations of multi-scale discrete analysis the pulses of a particular time period （points） and the space domain signal by numerical method were gotten, and the paper concluded that the signal singularity in load rupture had closely relations with fracture and uniaxial compression. The detected position and the actual breaking point only differed at one sample point, the relative error was 6.82%, and there was no accumulative error. Thus it provided an effective method to solve the problem of instability analysis of the signal singularity detection and coal-rock compression failure in the whole process.
基金Project supported by the Office of Naval Research,the Army Research Office and the National Science Foundation (No.DMS-0907931)
文摘The authors consider the multidimensional aggregation equation tp-div（p K＊ ρ） = 0 in which the radially symmetric attractive interaction kernel has a mild singularity at the origin （Lipschitz or better）, and review recent results on this problem concerning well-posedness of nonnegative solutions and finite time blowup in multiple space dimensions depending on the behavior of the kernel at the origin. The problem with bounded initial data, data in L^p ∩ L^1, and measure solutions are also considered.
基金Supported by National Natural Science Foundation of China under Grant Nos. 11045006,11135011the Chinese Academy of Sciences Key Project Y12A0A0012
文摘The color-flavor locked(CFL) strangelets have been investigated in a new quark model with linear confinement and one-gluon-exchange interactions.Considering Coulomb energy,we have studied the properties of three kinds of CFL strangelets,namely,positively charged,negatively charged and nearly neutral CFL strangelets.It is found that the one-gluon-exchange effect lowers the energy of a strangelet considerably and thus makes it much more stable than without considering the effect.The charge of a positive strangelet is larger than 0.15A 2/3 with A being the baryon number,but smaller than that in bag model.The charge of a negatively charged or nearly neutral CFL strangelet is nearly proportional to A 1/3.
