For a double array of blockwise M-dependent random variables {Xmn,m ≥ 1,n ≥ 1}, ∑i^m=1 ∑^nj=1 strong laws of large numbers are established for double sums ∑m i=1 ∑j^n=1 ij, m≥ 1, n 〉 1. The main results are ob...For a double array of blockwise M-dependent random variables {Xmn,m ≥ 1,n ≥ 1}, ∑i^m=1 ∑^nj=1 strong laws of large numbers are established for double sums ∑m i=1 ∑j^n=1 ij, m≥ 1, n 〉 1. The main results are obtained for (i) random variables {Xmn, m≥ 1, n ≥ 1} being non-identically distributed but satisfy a condition on the summability condition for the moments and (ii) random variables {Xmn, m ≥ 1, n ≥ 1} being stochastically dominated. The result in Case (i) generalizes the main result of M6ricz et al. [J. Theoret. Probab., 21, 660-671 (2008)] from dyadic to arbitrary blocks, whereas the result in Case (ii) extends a result of Gut [Ann. Probab., 6, 469-482 (1978)] to the bockwise M-dependent setting. The sharpness of the results is illustrated by some examples.展开更多
The aim of this paper is to prove the well-posedness(existence and uniqueness) of the L p entropy solution to the homogeneous Dirichlet problems for the anisotropic degenerate parabolic-hyperbolic equations with L p...The aim of this paper is to prove the well-posedness(existence and uniqueness) of the L p entropy solution to the homogeneous Dirichlet problems for the anisotropic degenerate parabolic-hyperbolic equations with L p initial value.We use the device of doubling variables and some technical analysis to prove the uniqueness result.Moreover we can prove that the L p entropy solution can be obtained as the limit of solutions of the corresponding regularized equations of nondegenerate parabolic type.展开更多
The numerical analysis for the matching of the core driven compression system in a double bypass variable cycle engine was presented in this paper.The system consists of a one-stage-core driven fan stage(CDFS),an inne...The numerical analysis for the matching of the core driven compression system in a double bypass variable cycle engine was presented in this paper.The system consists of a one-stage-core driven fan stage(CDFS),an inner bypass duct and a five-stage high pressure compressor(HPC),providing two basic operating modes: the single bypass mode and the double bypass mode.Variable vanes are necessary to realize the mode switch of the system.The correct matching in the double bypass mode requires a proper combination of the mass flow,total pressure ratio and blade speed.The work capacity of the system decreases in the double bypass mode and the pressure ratio tends to decrease more for the CDFS and the front stages of the HPC.The overall system efficiency is higher in the double bypass mode.The radial distributions of aerodynamic parameters are similar in different modes.The notable redistribution of mass flow downstream the CDFS in the single bypass mode leads to strong radial flows and additional mixing losses.The absolute flow angles into the inner bypass increase for the inner span and decrease for the outer span when the system is switched from the single bypass mode to the double bypass mode.展开更多
Consider the initial boundary value problem of the strong degenerate parabolic equation ?_(xx)u + u?_yu-?_tu = f(x, y, t, u),(x, y, t) ∈ Q_T = Ω×(0, T)with a homogeneous boundary condition. By introducing a new...Consider the initial boundary value problem of the strong degenerate parabolic equation ?_(xx)u + u?_yu-?_tu = f(x, y, t, u),(x, y, t) ∈ Q_T = Ω×(0, T)with a homogeneous boundary condition. By introducing a new kind of entropy solution, according to Oleinik rules, the partial boundary condition is given to assure the well-posedness of the problem. By the parabolic regularization method, the uniform estimate of the gradient is obtained, and by using Kolmogoroff 's theorem, the solvability of the equation is obtained in BV(Q_T) sense. The stability of the solutions is obtained by Kruzkov's double variables method.展开更多
A 14-bit,40-MHz analog front end(AFE) for CCD scanners is analyzed and designed.The proposed system incorporates a digitally controlled wideband variable gain amplifier(VGA) with nearly 42 dB gain range,a correlat...A 14-bit,40-MHz analog front end(AFE) for CCD scanners is analyzed and designed.The proposed system incorporates a digitally controlled wideband variable gain amplifier(VGA) with nearly 42 dB gain range,a correlated double sampler(CDS) with programmable gain functionality,a 14-bit analog-to-digital converter and a programmable timing core.To achieve the maximum dynamic range,the VGA proposed here can linearly amplify the input signal in a gain range from-1.08 to 41.06 dB in 6.02 dB step with a constant bandwidth.A novel CDS takes image information out of noise,and further amplifies the signal accurately in a gain range from 0 to 18 dB in0.035 dB step.A 14-bit ADC is adopted to quantify the analog signal with optimization in power and linearity.An internal timing core can provide flexible timing for CCD arrays,CDS and ADC.The proposed AFE was fabricated in SMIC 0.18 μm CMOS process.The whole circuit occupied an active area of 2.8×4.8 mm^2 and consumed360 mW.When the frequency of input signal is 6.069 MHz,and the sampling frequency is 40 MHz,the signal to noise and distortion(SNDR) is 70.3 dB,the effective number of bits is 11.39 bit.展开更多
文摘For a double array of blockwise M-dependent random variables {Xmn,m ≥ 1,n ≥ 1}, ∑i^m=1 ∑^nj=1 strong laws of large numbers are established for double sums ∑m i=1 ∑j^n=1 ij, m≥ 1, n 〉 1. The main results are obtained for (i) random variables {Xmn, m≥ 1, n ≥ 1} being non-identically distributed but satisfy a condition on the summability condition for the moments and (ii) random variables {Xmn, m ≥ 1, n ≥ 1} being stochastically dominated. The result in Case (i) generalizes the main result of M6ricz et al. [J. Theoret. Probab., 21, 660-671 (2008)] from dyadic to arbitrary blocks, whereas the result in Case (ii) extends a result of Gut [Ann. Probab., 6, 469-482 (1978)] to the bockwise M-dependent setting. The sharpness of the results is illustrated by some examples.
基金Yachun Li’s research was supported partly by National Natural Science Foundation of China (10571120,10971135)the Program for New Century Excellent Talents of Chinese Ministry of Education (NCET-07-0546)+3 种基金Shanghai Shuguang Project 06SG11Zhigang Wang’s research was supported partly by Shanghai Jiao Tong University Innovation Fund For Postgraduates (AE071202)the University Young Teacher Sciences Foundation of Anhui Province (2010SQRL145)the Quality Project Found of Fuyang Normal College (2010JPKC07)
文摘The aim of this paper is to prove the well-posedness(existence and uniqueness) of the L p entropy solution to the homogeneous Dirichlet problems for the anisotropic degenerate parabolic-hyperbolic equations with L p initial value.We use the device of doubling variables and some technical analysis to prove the uniqueness result.Moreover we can prove that the L p entropy solution can be obtained as the limit of solutions of the corresponding regularized equations of nondegenerate parabolic type.
文摘The numerical analysis for the matching of the core driven compression system in a double bypass variable cycle engine was presented in this paper.The system consists of a one-stage-core driven fan stage(CDFS),an inner bypass duct and a five-stage high pressure compressor(HPC),providing two basic operating modes: the single bypass mode and the double bypass mode.Variable vanes are necessary to realize the mode switch of the system.The correct matching in the double bypass mode requires a proper combination of the mass flow,total pressure ratio and blade speed.The work capacity of the system decreases in the double bypass mode and the pressure ratio tends to decrease more for the CDFS and the front stages of the HPC.The overall system efficiency is higher in the double bypass mode.The radial distributions of aerodynamic parameters are similar in different modes.The notable redistribution of mass flow downstream the CDFS in the single bypass mode leads to strong radial flows and additional mixing losses.The absolute flow angles into the inner bypass increase for the inner span and decrease for the outer span when the system is switched from the single bypass mode to the double bypass mode.
基金supported by the National Natural Science Foundation of China(No.11371297)the Science Foundation of Xiamen University of Technology(No.XYK201448)
文摘Consider the initial boundary value problem of the strong degenerate parabolic equation ?_(xx)u + u?_yu-?_tu = f(x, y, t, u),(x, y, t) ∈ Q_T = Ω×(0, T)with a homogeneous boundary condition. By introducing a new kind of entropy solution, according to Oleinik rules, the partial boundary condition is given to assure the well-posedness of the problem. By the parabolic regularization method, the uniform estimate of the gradient is obtained, and by using Kolmogoroff 's theorem, the solvability of the equation is obtained in BV(Q_T) sense. The stability of the solutions is obtained by Kruzkov's double variables method.
基金supported by the National Natural Science Foundation of China (Nos. 61234002, 61322405, 61306044, 61376033)the National High-Tech Program of China (No. 2013AA014103)the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory (No. ZHD201302)
文摘A 14-bit,40-MHz analog front end(AFE) for CCD scanners is analyzed and designed.The proposed system incorporates a digitally controlled wideband variable gain amplifier(VGA) with nearly 42 dB gain range,a correlated double sampler(CDS) with programmable gain functionality,a 14-bit analog-to-digital converter and a programmable timing core.To achieve the maximum dynamic range,the VGA proposed here can linearly amplify the input signal in a gain range from-1.08 to 41.06 dB in 6.02 dB step with a constant bandwidth.A novel CDS takes image information out of noise,and further amplifies the signal accurately in a gain range from 0 to 18 dB in0.035 dB step.A 14-bit ADC is adopted to quantify the analog signal with optimization in power and linearity.An internal timing core can provide flexible timing for CCD arrays,CDS and ADC.The proposed AFE was fabricated in SMIC 0.18 μm CMOS process.The whole circuit occupied an active area of 2.8×4.8 mm^2 and consumed360 mW.When the frequency of input signal is 6.069 MHz,and the sampling frequency is 40 MHz,the signal to noise and distortion(SNDR) is 70.3 dB,the effective number of bits is 11.39 bit.