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901.
Graphical models have been employed in a wide variety of computer vision tasks. Assignments of latent variables in typical models usually suffer the confused explanation in sampling way. In this paper we present discriminative sequential association Latent Dirichlet Allocation, a novel statistical model for the task of visual recognition, and especially focus on the case of few training examples. By introducing the switching variables and formulating the direct discriminative analysis, the sequential associations are considered as priori to establish a relevance determination mechanism to obtain the reasonable assignments of latent variables and avoid the invalid labeling oscillations. We demonstrate the power of our model on two common-used datasets, and the experiment results show that our model can achieve better performances with efficient convergence and give well interpretations of specific topic assignments at the same time.  相似文献   
902.
We propose a four-state quantum key distribution (QKD) scheme using generalized measurement of nonorthogonal states, the maximum mutual information measurement strategy. Then, we analyze the eavesdropping process in intercept–resend and photon number splitting attack scenes. Our analysis shows that in the intercept–resend and photon number splitting attack eavesdropping scenes, our scheme is more secure than BB84 protocol and has higher key generation rate which may be applied to high-density QKD.  相似文献   
903.
904.
Employing a polarization-entangled \(\chi \) state, which is a four-photon genuine entangled state, we propose a protocol teleporting a general two-photon polarization state. Firstly, the sender needs to perform one Controlled-NOT gate, one Hadamard gate, and one Controlled-NOT gate on the state to be teleported in succession. Secondly, the sender performs local nondemolition parity analyses based on cross-Kerr nonlinearities and publicizes the achieved outcomes. Finally, conditioned on the sender’s analysis outcomes, the receiver executes the single-photon unitary transformation operations on his own photons to obtain the state originally sit in the sender’s location. Due to the employment of nondemolition parity analyses rather than four-qubit joint measurement, it can be realized more feasible with currently available technologies. Moreover, the resources of Bell states can be achieved because the nondestructive measurement is exploited, which facilitates other potential tasks of quantum information processing.  相似文献   
905.
An integrated co-evolution model with the consideration of land use and traffic network design is proposed in this paper. In the suggested model, two kinds of economic agents are considered. On the one hand, the government makes the investment decision for the traffic network improvement based on the current traffic condition under the limited budget. On the other hand, households and companies will choose their locations according to the attraction of each traffic zone related to the road network accessibility and the housing price. Therefore, the land use is indicated by the population and employment distributions through the evolution process. Besides, the improvement of road capacity is modeled by a general bi-level programming of traffic network design. Simulation experiments show that the city will be more efficient and will have higher average accessibility for employment and population in the evolution process.  相似文献   
906.
This paper is concerned with the mean-square exponential stability problem for a class of impulsive stochastic systems with delayed impulses. The delays exhibit in both continuous subsystem and discrete subsystem. By constructing piecewise time-varying Lyapunov functions and Razumikhin technique, sufficient conditions are derived which guarantee the mean-square exponential stability for impulsive stochastic delay system. It is shown that the obtained stability conditions depend both on the lower bound and the upper bound of impulsive intervals, and the stability of system is robust with regard to sufficiently small impulse input delays. Finally, two examples are proposed to verify the efficiency of the proposed results.  相似文献   
907.
The paper is concerned with the problem of positive L 1-gain filter design for positive continuous-time Markovian jump systems with partly known transition rates. Our aim is to design a positive full-order filter such that the corresponding filtering error system is positive and stochastically stable with L 1-gain performance. By applying a linear co-positive Lyapunov function and free-connection weighting vectors, the desired positive L 1-gain filter is provided. The obtained theoretical results are demonstrated by numerical examples.  相似文献   
908.
909.
圆感应同步器是一种高精度角度传感器,传统的圆感应同步器的转子需外引激励线以驱动其工作,鉴于圆感应同步器在使用过程中需要连续旋转,这将使得外引激励线存在绞线的问题,本文提出一种新的设计方法,在圆感应同步器的定、转子基体上嵌有环状的金属导磁槽,导磁槽内放入环状金属导线.通过给定子导磁槽内的环状金属导线施加激励信号,此激励信号可耦合到转子导磁槽内的环状金属导线中以驱动转子工作,这使得转子无需外引激励线,进而提高了系统应用的便利性以及可靠性.  相似文献   
910.
在对公交收费系统的发展和无线射频识别技术进行研究的基础上,分析了现行公交收费系统的优缺点与局限性,并提出了一种公交车远卡自动收费系统的设计思路.主要使用ARM核芯片STM32、射频芯片nRF24LE1等器件,完成了硬件设计.在软件设计上实现了自动计算票价的扣费机制.该系统创新性地将远距离射频技术应用在公交收费系统中,不仅方便了乘客,而且大大提高了乘客上下车的效率.  相似文献   
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