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【期刊论文】Electronic excited-state transport with infrared divergence in disordered systems
邓辉舫, Deng Hui-fang
PHYSICAL REVIEW B VOLUME 36, NUMBER 12 15 OCTOBER 1987-11,-0001,():
-1年11月30日
On the basis of a new physical picture universally valid for all condensed matter of the infrared-divergence theory and starting from a non-Markovian process, the author investigates electronic excited-state or exciton transfer in disordered systems. The obtained results indicate that the present picture, which differs from the traditional Markovian-transport picture, is more reasonable and more universal than other existing theories. The theoretical predictions are in good agreement with the experimental investigation.
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邓辉舫, Deng Hui-fang
PHYSICAL REVIEW B VOLUME 37, NUMBER 4 1 FEBRUARY 1989,-0001,():
-1年11月30日
In this paper, a novel waiting-time distribution function (WTDF), ψ(t), which is not purely ex- ponential and is universally valid for explaining recently the low-frequency (say, w<10GHz) fluc- tuation, dissipation, and relaxation properties of condensed matter, is used to discuss asymptotic solutions of the continuous-time random-walk (CTRW) problems. Many results of theoretical and experimental interest are obtained. These results include the mean displacement, the dispersive mobility, the mean-squared displacement, the dispersive diffusion coefficient, the Nernst-Einstein relation, the variance and the standard variance, the lattice statistics, the initial-site occupation probability, the dispersive conductivity, the dispersive electrical transport, and the memory func- tion. All results show that the CTRW process described by the WTDF (t) appears to be non- Markovian over the very broad time domain and is Markovian only in the long-time limit; in oth- er words, all results contain a single parameter n, the infrared divergence exponent, which depends on the microscopic structure of condensed matter and governs the degree of dispersion. The larger the value of n, the stronger the dispersion. When n=0, the dispersion disappears and all results reduce immediately to the classical Markovian forms. This is in agreement with some ex- perimental facts.
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邓辉舫, Hui-fang DengH and J W Steeds
Semicond. Sci. Technol. 7(1992)125-134. Printed in the UK,-0001,():
-1年11月30日
In this paper, the effects are examined of the upper and the lower sulface recombinationv elocities, SI,S z, the diffusion length of excess minority carriers, L, and the thickness of the sample, h. on the minority carrier concentration profile (MCCPa) nd on the intensity of cathodoluminescence (CL) from thin foils. A systematic theoretical investigation of these effects is essential lo the understanding of experimental resuits which have recently been obtained by high-resolution CL imaging studies. By solving the reduced one-dimensional steady-stale diffusion equation under the non-trivial and realistic boundary conditions that the recombination velocities SI and Sp on the upper and lower surfaces are allowed lo vary independently of each other, exact and anaiyiical expressions for the MCCP and CL intensity (cu) are oblained for the general case of sulface recombination (sR). A number of special SR cases are discussed. The important question of the thickness dependence of the CL is addressed. Conditions for linear, square or cubic dependence of cu on h are deduced together with expressions for a thickness which we call the cut-off thickness. The capability of using the present analytical resun for MCCP to treat the electronbeam- induced current problem here is pointed out in passing together wlh TEM or STEM charge collection imaging and contrast problems of dislocations or defects. Specific numerical calculations are used to display the theoretical resuits quanlilalively and reveal a variety of properties of the model controlled by different values of the parameters contained within it. The resuits obtained can be used to explain and examine the features of CL in thin-film materials when examined in TEM or STEM modes. in some given cases, experimental determinations of the parameters can be made:
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【期刊论文】Tuning PUPID Active Queue Management ControllersSupporting TCP/IP Flows
邓辉舫, Yuedong Xu, HuifangDeng, Pingjian Zhang
,-0001,():
-1年11月30日
The Active Queue Management (AQM) strategies are important in Internet congestion control, which bear the PmIlPlD Structure esscntially. But it is hard to configure thc controlling parameters to achieve good tradcoff among a series of,$erformancc objectives. In this paper, we derivc the approximate First Order Lag Plus Delay (FOLPD) model of TCP/AQM and present a guideline to design PIPID, AQM in. the network routers. Both positional and incremental PIIPTDd: implementations arc considered. Simulation results manifest the effectiveness of thc proposed tuning method.
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【期刊论文】On the Value of Two-person Zero-sum Linear Quadratic DifferentialGames
邓辉舫, Pingjian Zhang, Huifang Deng, Jianqing Xi
IEEE Conference on Decision and Control, and the European Control Conference 2005 Seville, Spain, December 12-15, 2005,-0001,():
-1年11月30日
Considered in this paper are the two-person zerosumlinear quadratic differential games. It is shown that thevalue of the game exists if and only if both the upper value andlower value exist. As an consequence, we prove that anothernecessary and sufficient condition for the existence of the valueof the game is the existence of an open loop-open loop saddlepoint. An example is also given where lower value exists butupper value does not exist.
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