短波chirp探测的遗传退火频率分配算法研究

针对短波chirp探测系统的通信网络频率分配问题,建立了合理的干扰模型;利用系统所提供的测量参数,结合基本遗传算法,同时进行模拟退火操作以克服基本遗传算法易陷入局部最优解的不足,并最终趋于全局最优化;仿真结果表明,该算法在寻优性、收敛速度和稳定性等方面都要优于基本遗传算法。     

单参数控制的数字DC-DC变换器设计及其FPGA实现

传统的数字DC-DC变换器采用多参数控制方法,因而增加了控制器设计的复杂度和硬件开销;一种单参数控制的数字变换器控制方法被提出,其数字补偿器由一个乘法查找表和一个加法器构成,使得执行数字控制律的逻辑电路得到显著简化;在分析了控制参数对变换器性能的影响后,提出了获得系统最佳瞬态性能的设计条件;基于所提的单参数控制方法,完成了数字Buck变换器的FPGA实现,测试结果表明:在1MHz的开关频率下,对于1.8V的输出电压,电压纹波律小于1%,电压调整率为6mV/V,负载调节律为8mV/A;负载电流为0.3A时,转换效率高达91.9%。     

两类实现ARM系统VGA显示设计的对比

ARM系统的VGA显示主流方案直接利用Video DAC来实现,同时也出现了另外一种利用FPGA或者CPLD来实现ARM系统VGA显示的方案,且其视频转换效果较第一种明显提高.新的设计方案稍加改进就可以实现手机等其他嵌入式系统的VGA输出.本文阐述了两类设计方案,并且给出了测试结果和对比分析.     

常见计算机窃密技术分析及安全防范措施

随着信息化和网络技术的不断发展,以计算机为工具来盗取用户信息的犯罪日益增加。尤其是通过网络窃取上网计算机涉密信息,已经成为国内外不法分子窃取我国秘密信息的重要手段。本文对国内外计算机窃密与反窃密技术的各种手段进行研究与分析,并通过理论与实际的相结合,提出安全与实用并重的防范措施。     

Business process design: Process comparison and integration

This paper proposes a framework for business process design, which is based on process comparison and integration. This framework supports process stakeholders to model business processes collaboratively, which can greatly enhance the efficiency and effectiveness of business process design. By applying this framework, each process stakeholder can create his or her own model of the business process. The different models of the same business process can be automatically compared to find the conflicts between them. Based on the conflicts, process stakeholders can collaborate to improve the models. Then the models can be integrated to form a more complete model.     

A fast two-step block type decision algorithm for intra prediction in H.264/AVC high profile

Intra coding in H.264/AVC can significantly improve the compression efficiency but at the cost of high computational complexity. To reduce the complexity, this paper presents an efficient block type decision algorithm for intra prediction. In H.264/AVC high profile, three kinds of block types are supported. This algorithm determines the optimal block type by two steps. The first step is based on the fact that the block type of intra prediction is highly dependent on the smoothness of macroblock. An edge-based feature is introduced to characterize the smoothness, by comparing it with two thresholds impossible block type is firstly filtered out. Then the second step is based on the correlation of block type chosen for different chroma modes. Experimental results show that the proposed fast algorithm can achieve 72.8% time saving on average for encoding the all intra-frame sequence with average 0.75% bit rate increase and 0.05dB PSNR degradation when comparing with the reference software.     

A power-free deposited microbead plug-based microfluidic chip for whole-blood immunoassay

We present a deposited microbead plug (DMBP)-based microfluidic chip capable of performing plasma extraction and on-chip immunoassay. The DMBP used as a porous blood filter provides pure blood plasma without the contamination of blood cells or beads. Capillary-driven flow eliminates the requirement of external pumps. The human IgG and goat anti-human IgG sample-to-answer assay was performed in this chip within 600 s using only a 10 μl whole-blood sample. This easy-to-use, rapid, inexpensive, and disposable DMBP-based chip holds a great promise for point-of-care application.     

Topology optimization of free vibrating continuum structures based on the element free Galerkin method

In this paper, the topology optimization design of the free vibrating continuum structures is formulated based on the element free Galerkin (EFG) method. Considering the relative density of nodes as design variable, and the maximization of the fundamental eigenvalue as an objective function, the mathematical formulation of the topology optimization model is developed using the solid isotropic microstructures with penalization (SIMP) interpolation scheme. The topology optimization problem is solved by the optimality criteria method. Finally, the feasibility and efficiency of the proposed method are illustrated with several 2D examples that are widely used in the topology optimization design.     

非部分嵌套信息结构的LQG动态队决策问题的可解性（II）*

本文讨论非嵌套信息结构的递阶队决策问题和控制均享信息结构的LQG分散控制问题,文中首先证明这两类问题的信息结构都是“部分控制嵌入”的,进而给出最优策略(或控制)存在的充要条件和当此条件成立时最优策略(或控制)的表达式。     

标准正面人脸图像的识别

本论文选用人脸上27个特殊点作为人脸基本特征。以人脸几何结构为基础,结合有脸识别的心理特性,提出新颖、简便、高精度的“寻找存在”法,使提取特征点的速度、精度得到大大的提高,在详细分析这27个特列点的统计特性后,选择了其中信息量丰富的15个点间距及间距比构成一组向量代替人脸描述,用加权欧氏距离作为特征向量间相似性测试,在两类实验中,识别率高达100％和98％。