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991.
Junfeng Jiang Zhigang Cao 《Frontiers of Electrical and Electronic Engineering in China》2009,4(2):145-148
The acknowledged mode radio link control (AM-RLC) protocol is one of the most important radio protocols in wideband code division
multiple access (WCDMA) and time division-synchronization code division multiple access (TD-SCDMA) mobile communication systems.
A modified AM-RLC scheme with adaptive acknowledgement interval is proposed. At the receiver, the acknowledgement interval
is dynamically changed according to the channel status. The simulation results show that the proposed AM-RLC scheme outperforms
the fixed acknowledgement interval AM-RLC scheme in terms of frame delivery delay and protocol overhead.
__________
Translated from Journal on Communications, 2008, 29(3): 119–122 [译自: 通信学报] 相似文献
992.
993.
994.
995.
《半导体学报》2009,30(12)
Nonlinearity caused by the clock feed-through of a bootstrapped switch and its compensation techniques are analyzed. All kinds of clock feed-through compensation configurations and their drawbacks are also investigated.It is pointed out that the delay path match of the clock boosting circuit is the critical factor that affects the effective-ness of clock feed-through compensation. Based on that, a new clock feed-through compensation configuration and corresponding bootstrapped switch are presented and designed optimally with the UMC mixed-mode/RF 0.18μm 1P6M P-sub twin-well CMOS process by orientating and elaborately designing the switch MOSFETs that influence the delay path match of the clock boosting circuit. HSPICE simulation results show that the proposed clock feed-through compensation configuration can not only enhance the sampling accuracy under variations of process, power supply voltage, temperature and capacitors but also decrease the even harmonic, high-order odd harmonic and THD on the whole effectively. 相似文献
996.
Effects of exo-electron emission from MgO thin film on statistical delay of glow discharge of ac-PDP
Cho-Rong Hong 《Thin solid films》2009,517(14):4170-4173
Relationship between exo-electron emission currents and statistical delay of glow discharges of ac-PDP was investigated by measuring exo-electron currents. The currents were measured as a function of time and doping elements. The measured results indicated that the exo-electron currents decrease exponentially with time, while the statistical delay increases with time. The results demonstrate that the statistical discharge delay is inversely proportional to the currents of exo-electron emission from MgO film in a time interval of 1 to 10 ms. 相似文献
997.
Pieter W Uys Paul D van Helden John W Hargrove 《Journal of the Royal Society Interface》2009,6(30):11-15
In a significant number of instances, an episode of tuberculosis can be attributed to a reinfection event. Because reinfection is more likely in high incidence regions than in regions of low incidence, more tuberculosis (TB) cases due to reinfection could be expected in high-incidence regions than in low-incidence regions. Empirical data from regions with various incidence rates appear to confirm the conjecture that, in fact, the incidence rate due to reinfection only, as a proportion of all cases, correlates with the logarithm of the incidence rate, rather than with the incidence rate itself. A theoretical model that supports this conjecture is presented. A Markov model was used to obtain a relationship between incidence and reinfection rates. It was assumed in this model that the rate of reinfection is a multiple, ρ (the reinfection factor), of the rate of first-time infection, λ. The results obtained show a relationship between the proportion of cases due to reinfection and the rate of incidence that is approximately logarithmic for a range of values of the incidence rate typical of those observed in communities across the globe. A value of ρ is determined such that the relationship between the proportion of cases due to reinfection and the logarithm of the incidence rate closely correlates with empirical data. From a purely theoretical investigation, it is shown that a simple relationship can be expected between the logarithm of the incidence rates and the proportions of cases due to reinfection after a prior episode of TB. This relationship is sustained by a rate of reinfection that is higher than the rate of first-time infection and this latter consideration underscores the great importance of monitoring recovered TB cases for repeat disease episodes, especially in regions where TB incidence is high. Awareness of this may assist in attempts to control the epidemic. 相似文献
998.
The paper considers the estimation of error in the time correlation of measurements in relation to state determination for
a dynamic system. An algorithm has been devised for a joint estimation of the object state vector and the time correlation
error, which is based on a modification of a Kalman filtration dynamic algorithm.
Translated from Izmeritel’naya Tekhnika, No. 4, pp. 10–12, April, 2009. 相似文献
999.
1000.
This paper investigates the problem of robust stabilization and attenuation for a class of uncertain networked control systems
(NCSs) with random communication network-induced delays. Based on the Lyapunov–Razumikhin method, a controller is designed
such that both robust stability and a prescribed disturbance attenuation performance for the closed-loop NCS are achieved,
irrespective of the uncertainties and network-induced delays. The controller design technique is given in terms of the solvability
of bilinear matrix inequalities. An iterative algorithm is proposed to change this non-convex problem into quasi-convex optimization
problems, which can be solved effectively using available mathematical tools. The effectiveness of the proposed design methodology
is verified by a numerical example. 相似文献