高速无线通信系统中自适应均衡技术研究     

孙俊杰  鄢妍 《江西电力职业技术学院学报》2008,21(4)

首先介绍常见均衡器的结构和自适应算法,然后指出基于RLS自适应算法的判决反馈均衡器可以有较快的收敛速度,同时有较好的均衡效果,并通过Matlab仿真证明。  相似文献   

基于网络的颜色图像检索系统设计     

廖东进 《南宁职业技术学院学报》2008,13(2):95-97

传统的基于颜色直方图的图像检索方法丢失了颜色空间分布信息,根据提出来的一种分块加权颜色直方图的图像检索方法,通过Visual Studio.Net 2003编程实现了在网络中基于颜色的图像检索系统的设计,并对该系统的检索效果和性能进行了详细分析。实验结果表明该系统具有较好的检索效果和性能。  相似文献   

基于教师评定的留守儿童学校适应特点     

彭文波  高亚兵 《浙江教育学院学报》2008,(5):35-42

采用学生学校适应教师评定量表对650名留守儿童和698名非留守儿童进行研究,发现：留守儿童学校适应的总体水平极其显著低于非留守儿童,在适应良好的学生中,留守儿童显著少于非留守儿童;留守儿童积极完成学校任务、人际自表与交往信心显著低于非留守儿童,而学习中的消极行为、学校问题行。为以及不良社交问题显著多于非留守儿童;不同性别、学段、学习成绩留守儿童学校适应差异性显著,监护的不同对学校适应影响不明显;留守儿童中,男生、初中生、学业成绩不良学生应得到更多的关注和引导。  相似文献   

Environment map building and localization for robot navigation based on image sequences     

Ye-hu Shen  Ji-lin Liu  Xin Du 《浙江大学学报(A卷英文版)》2008,9(4):489-499

SLAM is one of the most important components in robot navigation. A SLAM algorithm based on image sequences captured by a single digital camera is proposed in this paper. By this algorithm, SIFT feature points are selected and matched between image pairs sequentially. After three images have been captured, the environment＇s 3D map and the camera＇s positions are initialized based on matched feature points and intrinsic parameters of the camera. A robust method is applied to estimate the position and orientation of the camera in the forthcoming images. Finally, a robust adaptive bundle adjustment algorithm is adopted to optimize the environment＇s 3D map and the camera＇s positions simultaneously. Results of quantitative and qualitative experiments show that our algorithm can reconstruct the environment and localize the camera accurately and efficiently.  相似文献   

基于FPGA的铁磁物质探测系统设计与研究     

曹海军  李丕丁 《教育技术导刊》2021,20(1):159-163

铁磁性物质对磁共振成像质量、设备安全和相关人员人身安全有着巨大威胁。传统金属检测仪敏感度不同,容易变化且不能分辨被测物是否为铁磁性。国外专用铁磁探测系统性能优异但技术保密严格且价格昂贵,而国内检测产品在灵敏度方面与之相比不占优势。基于FPGA的铁磁物质探测系统设计根据磁通门传感器测磁原理,采用平行式线圈结构,通过基于数字正交锁相放大的二次谐波法对采集的信号进行数字信号处理并对其进行自适应滤波算法处理以提高系统整体性能。实验测试结果表明,该系统较模拟式信号处理抗干扰能力强且使得铁磁性物质探测的灵敏度提高10.3%,实际探测距离由0.5m提高到1m。  相似文献   

基于移动通信行为的个体友谊圈的含权网络分析     

谭韬  陈永冰  邓明森 《贵州教育学院学报》2008,24(9):40-43

利用移动电话记录为依据研究了个体友谊圈,利用个体跟周围的人群之间使用移动电话联系的频率来刻画个体之间友谊的深厚程度,并以这种频率的高低来定义友谊的权重。通过计算发现,对于每个个体,他们的不同权重的朋友的数目服从指数为1的幂率分布,为建立个体友谊圈的含权网络提供了一种可能的模式。  相似文献   

Constructing normalcy: a qualitative study of parenting children with Asperger's Disorder     

Jon Lasser  Kristyn Corley 《Educational Psychology in Practice》2008,24(4):335-346

Children with Asperger's Disorder present unique challenges due to their impairments in social functioning. In order to better understand the experiences of parents of children with Asperger's Disorder, interviews were conducted with 20 parents. The interviews were taped, transcribed, and coded using the systematic methods of Grounded Theory. The central phenomenon of “constructing normalcy” emerged from the data as a salient construct for participants. Parents interviewed described a process of meaning‐making with respect to standards of “normalcy” and an effort to create adaptive environments for their children.  相似文献   

一种基于模糊模型相似测量的字符无监督分类法     

卢达  钱忆平  谢铭培  浦炜 《东南大学学报》2002,18(4)

提出了一种能有效完成对无监督字符分类的模糊逻辑方法 ,以提高字符识别系统的速度 ,正确性和鲁棒性 .字符首先被分为 8种印刷结构类 ,然后采用模式匹配方法将各类字符分别转换成基于一非线性加权相似函数的模糊样板集合 .模糊无监督字符的分类是字符匹配的一种自然范例并发展了加权模糊相似测量的研究 .本文讨论了该模糊模型的特性并用以加快字符分类处理 ,经过字符分类 ,在字符识别时由于只需针对较小的模糊样板集合而变得容易和快速  相似文献   

Latent Variable Modeling and Adaptive Testing for Experimental Cognitive Psychopathology Research     

Michael L. Thomas  Gregory G. Brown  Virginie M. Patt  John R. Duffy 《Educational and psychological measurement》2021,81(1):155

The adaptation of experimental cognitive tasks into measures that can be used to quantify neurocognitive outcomes in translational studies and clinical trials has become a key component of the strategy to address psychiatric and neurological disorders. Unfortunately, while most experimental cognitive tests have strong theoretical bases, they can have poor psychometric properties, leaving them vulnerable to measurement challenges that undermine their use in applied settings. Item response theory–based computerized adaptive testing has been proposed as a solution but has been limited in experimental and translational research due to its large sample requirements. We present a generalized latent variable model that, when combined with strong parametric assumptions based on mathematical cognitive models, permits the use of adaptive testing without large samples or the need to precalibrate item parameters. The approach is demonstrated using data from a common measure of working memory—the N-back task—collected across a diverse sample of participants. After evaluating dimensionality and model fit, we conducted a simulation study to compare adaptive versus nonadaptive testing. Computerized adaptive testing either made the task 36% more efficient or score estimates 23% more precise, when compared to nonadaptive testing. This proof-of-concept study demonstrates that latent variable modeling and adaptive testing can be used in experimental cognitive testing even with relatively small samples. Adaptive testing has the potential to improve the impact and replicability of findings from translational studies and clinical trials that use experimental cognitive tasks as outcome measures.  相似文献   

向量值的加权Herz型Hardy空间的原子分解     

张荣欣  刘文海  赵凯 《福建教育学院学报》2007,8(10):107-110

Herz型Hardy空间在Rn上的原子分解与分子分解理论研究已相当成熟,本文主要建立了向量值函数在加权Herz型Hardy空间上的原子分解理论的一个定理。  相似文献