Analysis of M-ary FSK square law combiner under Nakagami fadingconditions

M-ary FSK transmission with square law combining over frequency non-selective m-distributed Nakagami fading with arbitrary m is studied. A closed form of the symbol error probability is derived and is verified by simulation to be accurate     

Cluster-Based Saliency-Guided Content-Aware Image Retargeting

Straightforward image resizing operators without considering image contents (e.g., uniform scaling) cannot usually produce satisfactory results, while content-aware image retargeting aims to arbitrarily change image size while preserving visually prominent features. In this paper, a cluster-based saliency-guided seam carving algorithm for content-aware image retargeting is proposed. To cope with the main drawback of the original seam carving algorithm relying on only gradient-based image importance map, we integrate a gradient-based map and a cluster-based saliency map to generate a more reliable importance map, resulting in better single image retargeting results. Experimental results have demonstrated the efficacy of the proposed algorithm.     

Modeling node mobility for reliable packet delivery in mobile ip networks

In this paper, we analyze node mobility for reliable packet delivery in mobile IP networks. In mobile IP, packets destined to roaming nodes are intercepted by their home agents and delivered via tunneling to their care of addresses (CoA). A mobile node may roam across multiple subnets. At each boundary crossing, a handoff is initiated such that the CoA is updated and a new tunnel is established. We consider both basic mobile IP handoff and smooth handoff. We find that reliable packet delivery in mobile IP networks can be modeled as a renewal process, because the retransmission over a new tunnel after each boundary crossing is independent of the previous history. We then derive the probability distribution of boundary crossings for each successful packet, based on which the packet reliable delivery time can be obtained. Our analytical model is derived based on a general distribution of residence time in a subnet and a general distribution of successful retransmission attempts in each subnet. The results can be readily applied to any distributions for both items. We also provide numerical examples to calculate the probability distribution of boundary crossings, and conduct simulations to validate our analytical results     

吸收栅对光折变晶体钛酸铋中两波混合能量转移的影响

基于钛酸铋晶体的吸收系数依赖于入射光强,考虑吸收栅对它的两波混合能量转移的影响,在某些近似条件下,推导出稳态两波耦合作用的表达式,与实验结果作了比较。测量了纯吸收栅的增益,给出结果。     

P-表示为经典位相的位相算符

以其P-表示为经典位相的要求我们定义了一种新的位相算符表达式,并指出它与Susski-nd-Glogower相算符的异同。     

压缩真空态的另一表示

本文用正规乘积内积分法证明态矢exp(λQ~2)|0>(|0>是真空谐振子态,Q=1/2~(1/2)(a+a~+))在适当地选择λ后构成压缩真空态。     

帧同步码的在线误码率算法研究

本文将信道误码分布模型归结为简单泊松分布和复合泊松分布,在计算机大量模拟的基础上,提出了将帧同步码误码分段,采用最小二乘曲线拟合并修正,来获得更加准确可靠的系统信道实时误码率,为误码率的检测处理提供了新的思路和方法。并结合某数字微波电子抗干扰课题,提出了实施的具体方法和步骤。     

A composite-resonator mode description of coupled lasers

We investigated the behavior of two lasers operating with coupled resonators. Our analysis involves a decomposition of the laser field in terms of the passive composite resonator eigenmodes. The interaction between the laser field and the active medium is found to lead to mode coupling, The dominant coupling mechanism is cross saturation among composite-resonator modes. The effects of cross saturation on the output of the coupled lasers are investigated. Our results are valid for all values of coupling between lasers. Examples of lockbands calculated using the composite-resonator mode analysis are presented.     

大口径尾翼稳定脱壳穿甲弹全弹道优化设计

研究了应用现代最优化理论对弹炮系统进行多目标优化设计的基本方法和步骤。选用了约束变尺度法对高膛压滑炮配备尾翼稳定脱壳穿甲弹的装药结构和弹形结构参数进行多目标优化设计，得出了较满意的结果。     

弧厚不均火药在内弹道计算中的处理方法

根据所用粒状药内外弧厚不同的特点，推导了该粒状药二项式与三项式的形状函数，并进行了比较，建立了粒状药与管状药组成的混合装药的多相流内弹道理论模型，编制工程实用的软件系统，数值预报射击过程膛内物理量变化的详细结果，该研究结果对于指导装药设计，弹丸设计与身管设计都具有重要的理论参考价值与工程实际意义。