公度线网络双端匹配“实频技术”

本文在近几年发展的“实频技术”的基础上,提出了一种设计公度线结构双端宽带匹配网络的新方法——公度线网络双端匹配“实频技术”,并将它应用到了宽带、低噪微波多级放大器的设计中,编制了相应的CAD程序,给出了设计实例。

QoE-Aware Proportional Fair Scheduling for Multiuser Multiservice Wireless Networks

The effective radio resource allocation al-gorithms, which satisfy diversiform requirements of mobile naltimedia services in wireless cellular net-works, have recently attracted more and more at-tention. This paper proposes a service-aware scheduling algorithm, in which the Mean Opinion Score （MOS） is chosen as the unified metric of the Quality of Experience （QoE）. As the network needs to provide satisfactory services to all the users, the fairness of QoE should be considered. The Propor- tional Fair （PF） principle is adopted to achieve the trade-off between the network perfonmnce and us- er fairness. Then, an integer progranming problem is formed and the QoE-aware PF scheduling princi-ple is derived by solving the relaxed problem. Simu-lation results show that the proposed scheduling principle can perform better in terms of user fair-ness than the previous principle maximizing the sum of MOS. It also outperfoms the max-rain scheduling principle in terms of average MOS.

Method to determine parameters in the rainstorm intensity formula

This paper presents a new method to determine parameters in the nonlinear mathematical model of the urban rainfall intensity formula. The method transforms the nonlinear equation into a linear one, and incorperates a damping factor and a step factor to improve the precision of the calculated results. It works out the parameters based on given rainstorm intensity, period of the recurrence of rainstorm and lasting time of the rainfall. The results turns out to have the smallest residual error compared with those obtained by several other methods and satisfy the related standard. The method proves of fast convergence, desirable generality, stability and accuracy, which overcomes the defects of other existing numeral methods.

Distributed fair queuing algorithm based on compensation coordination scheduling in WMN

This paper proposes a distributed fair queuing algorithm which is based on compensation coordi- nation scheduling in wireless mesh networks, considering such problems as the location-dependent competition and unfair channel bandwidth allocation among nodes. The data communication process requiring the establishment of compensation coordination scheduling model is divided into three periods： the sending period, the compensation period and the dormancy period. According to model parameters, time constraint functions are designed to limit the execution length of each period. The algorithms guarantee that the nodes complete fair transmission of network packets together in accordance with the fixed coordination scheduling rule of the model. Simulations and analysis demonstrate the effectiveness of the proposed algorithm in network throughput and fairness.

Dynamic Bayesian identification of mechanical parameters of multi-cell curve box girder based on conjugate gradient theory

For multi-cell curve box girder, the finite strip governing equation was derived on the basis of Novozhilov theory and orthogonal property of harmonious function series. Dynamic Bayesian error function of mechanical parameters of multi-cell curve box girder was achieved with Bayesian statistical theory. The corresponding formulas of dynamic Bayesian expectation and variance were obtained. After the one-dimensional optimization search method for the automatic determination of step length of the mechanical parameter was put forward, the optimization identification calculative formulas were also obtained by adopting conjugate gradient method. Then the steps of dynamic Bayesian identification of mechanical parameters of multi-cell curve box girder were stated in detail. Through analysis of a classic example, the dynamic Bayesian identification processes of mechanical parameters are steadily convergent to the true values, which proves that dynamic Bayesian theory and conjugate gradient theory are suitable for the identification calculation and the compiled procedure is correct. It is of significance that the foreknown information of mechanical parameters should be set with reliable practical engineering experiences instead of arbitrary selection.

Time distribution characteristics of cat-eye reflected light from moving optical target

By using the Collins diffraction formula and expanding the aperture function into a fmite sum of complex Gaussian functions, an analytical formula of the time light intensity distribution for oblique Gaussian beams passing through a moving cat-eye optical lens and going back along the entrance way is deduced. By numerical computation, the variation laws of the time intensity distributions of the cat-eye reflected light with the viewing angle, imaging distance, aperture and instantaneous field of view are given. The results show that the relationship between the light intensity at the return place and the detection time is linear, and it is of inverse proportion only when the viewing angle is very large. For the staring imaging optical lens, the nonlinear extent of the time distribution curve becomes larger with the decrease of the viewing angle. For the instantaneous imaging optical lens, there is still some cat-eye reflected light when the detection system is out of the viewing field of the target lens.